Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1638 is perfect. Brilliant!

#1639. A can do a job in 9 days while B is twice as fast. In how many days would the same job done if they work together?

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.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,000

Hi ganesh

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym and anonimnystefy,

The solution #1639 is perfect. Good work!

#1640. If 20 workers can complete a task in 45 days, how many more workers would be required to complete it in 30 days?

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.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1640 is perfect. Neat work!

#1641. A is four times as good a workman as B and takes 12 days less to do a piece of work than B takes. In how many days B alone can do the whole work?

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.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1641 is correct. Neat work!

#1642. 25 men take 20 days to complete a certain work. 15 men left the work after some days. If the remaining work was completed in 37.5 days, after how many days did 15 men leave the work?

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1642 is perfect. Brilliant!

#1643. Find the prime factorization of the following numbers:

(a) 1152

(b) 1296

(c) 1440

(d) 1584

(e) 1728

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solutions (b), (c), and (d) are correct. Good work!

#1644. Given the Greatest Common Divisor (306, 657) = 9, find the Least Common Multiple (306, 657).

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1644 is correct. Neat work!

#1645. Find the Least common multiple and Greatest common divisor of 35, 48, 56 by applying the prime factorization method.

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1645 is perfect. Good work!

#1646. Solve : 4x - 3y - 8 = 0 and 6x - y - 29/3 = 0.

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1646 is correct. Good work!

#1647. Solve : 4x + 7y = 20 and x - 13y = 21.

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

#1648. Solve : 4x + 6/y = 15 and x - 8/y = 14.

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

#1649. Solve : 5x + 3y = 70 and 3x - 7y = 60.

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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 102,219

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,067

Hi bobbym,

The solution #1648 is correct; my aplology.

The solution #1649 is perfect. Brilliant!

#1650. Solve : x/2 - y/5 = 4 and x/7 + y/15 = 3.

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

Offline