Tuesday

July 29, 2014

July 29, 2014

Posted by **JOSHUA BAME** on Friday, November 26, 2010 at 5:41am.

IF THE DIFFERENCE BETWEEN THE 6TH AND 3RD TERM IS 12,

FIND THE:

COMMON DIFFERENCE,

1ST TERM,

20TH TERM.

- arithmetic progression -
**MathMate**, Friday, November 26, 2010 at 7:55amLet

d = the common difference

t(n)=nth term

t(6)-t(5)=d

t(5)-t(4)=d

t(4)-t(3)=d

Add

t(6)-t(3)=3d

or

3d=12

Solve for the common difference d=4

Sum of the 2nd and 5th terms = 42

t(2)+t(5)

=t(2)+(t(2)+3d)

=2*t(2)+12 = 42

Solve for t(2) = 15

t(1) should be t(2)-1=15-4=11

and

t(20)=t(1)+19d

**Related Questions**

Math - 1) If the sum of the first n terms of a series is Sn where Sn=2nē-n, (a)...

math - 1) If the sum of the first n terms of a series is Sn where Sn=2nē-n, (a)...

Arithmetic Progression - In an AP the 6th term is half the 4th term and the 3rd ...

arithmetic - In an arithmetic progression the sum of the first 10 terms is 50 ...

arithmetic - 1. The first and last term of an A.P are, a and l respectively, ...

arithmetic - 1. The first and last term of an A.P are, a and l respectively, ...

Mathematics - The 25 term of an Arithmetic Progression is 7 1/2 and the sum of ...

Precalculus - The 8th term in an arithmetic sequence is 5, and the sum of the ...

Math - Sum of4th and the 6th terms of an a,p is 42 . While the sum of the 3rd ...

Sequence - Find the common difference and a formula formula for the nth term of ...