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

You are not logged in.

- Topics: Active | Unanswered

Thanks Bobym that is it! And will do that in the future

Just question three [3]

the answer is at the back of the book and is 62 or 122 but need the steps

Thank Nehu!

Please-- how about the others?

Please help.

Good one

Hi, Please help with these;

It will help me understand any question regarding G.P and A.P

(1) The sum of the first three terms of a geometric sequence is 8 and the sum of the first six terms is 12. Find the the common ratio

(2) The sum of the first twelve of an A.P is 168. If the term is 7, find the values of

(i) the common difference

(ii) the first term

(3) the sum of the first 3 terms of a G.P is 14. If the term is 7, find the possible values of the sum of the first 5 terms

Please help me I got an exam by tomorrow many thanks.

**EbenezerSon**- Replies: 2

I posted G.P questions in this very forum and wanted to review it. But I'm taken aback 'cause I cannot find the thread anymore. The subject was ; Geometric progression. Hope Bobym and Bundy will help find it. I have an exam to write by tomorrow and had wanted to read the solutions. Please help

Yes sirrrrr!

Thank you!

2 right?

I go like this 14/3 = 4.666 then had k = 4.66.. then I plugged it into 3ab + a - 2b.

My final answer is 12.666666 correct?

I'm getting K = 4.666666667 correct?

So after these should I proceed to use the AP sum formula to calculate seperately for the 8th and the 20th term?

Thank you Bob!

**EbenezerSon**- Replies: 11

A few question,

(1)A binary operation is defined on the set of real numbers by a*b = 3ab + a - 2b

Find the value of K which satisfies the equation K * 3 = 14

How would you do this?

(2)Find the next four terms of the sequence given by Un = 3 + 2n for n = 1, 2 ,3 ,4

So is the following solution correct? 3 + 2(1) = 5

3 + 2(2) = 7

3 + 2(3) = 9

3 + 2(4) = 11.

Thank you all

So, one has to generate his own rule by using the numbers given? Or that rule you have given should always be used for such questions?

Again,

So, if the numbers have no common difference or ratio then I should resort to using the polynomials like the rule you have generated for the problem?

Hi Relentless,

How did you use the rule 0.5n^2 + 0.5n to answer question one? Please show working

**EbenezerSon**- Replies: 21

1) Determine the next three terms of the sequence ,1,3,6,10,

And my attempts as follows;

common difference, 3 - 1 = 2

firt term = 1, second term 1 + 2 = 3, third term 1 +2(2) = 5, fourth term 1 + 3(2) = 7, fith term 1 + 4(2) = 9, sixth term 1 + 5(2) = 11 and so on. Is these correct?

Again,

(2)Find the coefficient of X^2 in the expression (1 + x )^4.

My solution is [1, 4, 6, 4, 1] is that correct?

(3)Find the sum of the sequence of the natural numbers 1, 2, 3, 4,........25.

How are going to do this?

4) Write down the next three terms of the sequence 12, 18, ,27 , ,

Thanks!

I see now!

Thank you

In an arithmetic progression, the 8th term is twice the 4th and the 20th is 40.

Find the first term. the common difference and the sum of the terms from the 8th term to the 20th term inclusive.

I'm gettin hard time solving it, please let me see yous steps.

Please, work the problem so that I follow your steps.

Thanks

"I know only ...I know nothing" I have always loved this paradox. Thanks for the compliment. I used AP to calculate for the 9th year and had the answer. Should I use AP To find for the 12th year?

Many thanks!

**EbenezerSon**- Replies: 11

Hi Tutor;

On commencing employment a man is paid a salary of $720,000 per annum and receives annual increments of $35000, determine his salary in the 9th year and calculate the total salary he will receive in the first 12 yrs.

I had $1000000 as answer. But I'm getting hard time getting the common ratio so that it will help me use the GEOMETRIC PROGRESSION method to calculate for the first 12yrs.

Please help.

**EbenezerSon**- Replies: 2

Hi,

Tutor - please solve this one for me I'm confused;

5 sq of3 -3 sq of5/sq of5 - sq of3 - sq of5 - sq of3/5sq of3 - 3sq of3.

I should have latex it properly but dont know how to do that.

It is a surd question.

(sq of) means there is a principal square root sign.

Thanks!

The average test mark for a class of 21 students is 65. Peter's mark was recorded as 35 instead of 55. What is the correct average mark for the test?

I had 62.8571 as answer, is that correct?

**EbenezerSon**- Replies: 3

I'm a little bit bemused about the difference between grouped and ungrouped data.

Does a grouped data always have class intervals such as 0-9, 10-19...? Whiles an ungrouped data does not have such class intervals?

Please confirm, thank you in advance

**EbenezerSon**- Replies: 2

Hi,

How can one calculate for the one-tenth of $3200?

Thank you