reto wrote:

How many even multiples of 35 are there between 349 and 701?

A. 5

B. 6

C. 9

D. 10

E. 11

I found number of terms with \(\frac{Last - first}{increment}\) + 1, where n = 11 and the number of even multiples should outnumber the odd multiples by one: \(n_{even}\) = 6

But if you were stuck, the numbers here are few enough that you could list them.

We need EVEN multiples of 35 between 349 and 701.

The first one after 349 (that number is a big fat hint), is 350

350 + 35 = 385, but that's odd

385 + 35 = 420

That works. To get to the next even multiple after 350, you had to add 70.

Adding 35 to an even multiple yields odd (350 + 35). Adding 70 to an even multiple yields even (350 + 70). So just add 70 to the first multiple, keep adding 70, and stop when you're at < 701. Thus:

350

420

490

560

630

700

Done. There are 6 even multiples of 35 between 349 and 701.

Answer B

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