Question

Can someone please explain how to solve this SAT Math question?

Answer 1

a, 2a−1, 3a−2, 4a−3, ...

For a particular number a, the first term in the sequence above is equal to a, and each term thereafter is 7 greater than the previous term. What is the value of the 16th term in the sequence?

Answer 2

@sammixboo Can you please explain how to solve this?

Answer 3

you are given term is 7 more than the last term
that we could go ahead and solve for a
knowing that 2a-1 is 7 more than a
you have the equation 2a-1=a+7 (solve for a )

Answer 4

once we find a
then I think things will be more clearer to you

Answer 5

Could I do (2a-1)-a=7 ?

Answer 6

yes so you have 2a-a-1=7
and you can also add 1 on both sides
2a-a=7+1

Answer 7

Ohhh I see. Can you give me a similar problem to solve please?

Answer 8

but we aren't done with that problem

Answer 9

we are asked to find the 16th term not a

Answer 10

finding a will help us though

Answer 11

Yes, so the 16th term would be 113, right?

Answer 12

yep you are brilliant :)

Answer 13

a similar problem...
hmm...
one sec

Answer 14

You have the sequence: 1-a,2-2a,3-3a,4-4a,....
You are given that each term is 5 less than the previous term.
Find the 9th term.

Answer 15

So (1-a) - 5 = 2 - 2a ?

Answer 16

that is the exact equation I have setup :)

Answer 17

Did you get a=6?

Answer 18

yes

Answer 19

So the 9th term is -45?

Answer 20

totally what I got
great job

Answer 21

Yay! Thank you so much!! :)

Answer 22

np