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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 561 (two parts) is correct. Brilliant, bobbym!

562. The angle of elevation of the top of a tower from two points at a distance of 4 m and 9 m from the base of the tower and in the same straight line with it are complementary. Find the height of the tower.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 562 is correct. Excellent, bobbym!

563. A box contains 35 blue, 25 white, and 40 red marbles. If a marble is drawn at random from the box, find the probability that drawn marble is

a) white.

b) not blue.

c) neither white nor blue.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 563 (three parts) is correct. Excellent, bobbym!

564. Water is flowing at the rate of 15 kilometers per hour through a pipe of diameter 14 cm into a rectangular tank which is 50 m long and 44 m wide. Determine the time in which the level of water in the tank will rise by 7 cm.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 564 is correct. Marvelous, bobbym!

565. Sum of the areas of two squares is 640 square meters. The difference of their perimeters is 64 m. Find the sides of two squares.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 565 is correct. Neat work, bobbym!

566. Find the ratio in which the points (-3,k) divides the line segment joining the points (-5,-4) and (-2,3). Hence, find the value of k.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

*566. Find the ratio in which the points (-3,k) divides the line segment joining the points (-5,-4) and (-2,3). Hence, find the value of k.*

The latter part of your solution is perfect. Excellent, bobbym! Please reply the former part in order to post the complete solution, bobbym.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 566 is correct. Neat work, bobbym!

567. Find the number of coins 1.5 cm in diameter and 0.2 cm thick, to be melted to form a right circular cylinder of height 10 cm and diameter 4.5 cm.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 567 is correct. Excellent, bobbym!

568. A bag contains 5 red balls, 7 white balls, 5 green balls and 8 black balls. One ball is drawn at random from the bag. Find the probability the ball is

(i) white

(ii) red or black

(iii) not green

(iv) neither white nor black

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 568 (four parts) is correct. Excellent, bobbym!

569. Find an A.P. whose fourth term is 9 and the sum of its sixth term and thirteenth term is 40. (first four terms)

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 569 is correct. Neat work, bobbym!

570. From a point 100 m above a lake, the angle of elevations of a stationary helicopter is 30 degrees and the angle of depression of reflection of the helicopter in the lake is 60 degrees. Find the height of the helicopter.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 570 is correct. Excellent, bobbym!

571. One card is drawn from a well shuffled deck of 52 playing cards. Find the probability of getting

(i) a non-face card

(ii) a black king or a red queen

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solution 571 is correct. Excellent, bobbym!

572. (i) A box contains 5 red marbles, 8 white marbles and 4 green marbles. One marble is taken out of the box at random. What is the probability that the marble taken out will be

(i) red?

(ii) white?

(iii) not green?

572. (ii) There are 30 cards, of same size, in a bag on which numbers 1 to 30 are written. One card is drawn out of the bag at random. Find the probability that the number on the selected cards divisible by 3.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,432

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 22,555

Hi;

The solutions 572(i) and 572(ii) are correct. Excellent, bobbym!

573. Water is flowing through a cylindrical pipe, of internal diameter 2 cm, into a cylindrical tank of base radius 40 cm, at the rate of 0.4 cm m/s. Determine the rise in level of water in the tank in half an hour.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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