Question

(This is a question from arithmetic sequence) Jay’s dog weighs 35 kilograms and is overweight. The dog is put on a diet, losing 0.4kg

every week. How long does it take to reach the target weight of 28 kilograms?

Answer 1

17.6 weeks

Explanation:

The computation of the time taken to reach the target weight is shown below:

35, 34.6, 34.2...............28

As we know that

a_n = a + (n - 1)d

28 = 35 + (n - 1)(-0.4)

28 = 35 -0.4n + 0.4

28 = 35.04 - 0.4n

0.4n = 35.04 - 28

0.4n = 7.04

n = 17.6