Question

Chinedu sat down to do his homework, which included 30 math problems. He solved 2 problems each minute. Let f(n) be the number of problems left for Chinedu to solve at the beginning of the 9 th minute.

Answer 1

Answer: There are 14 math problems left at the beginning of 9th minute.

Explanation:

Since we have given that

Number of math problems he has = 30

Number of problems he solved each minute = 2

We need to find the number of problems left for Chinedu to solve at the beginning of the 9th minute.

That means number of questions he solved in 8 minutes will be deducted from the total number of questions.

Number of questions he solved in 8 minutes is given by

`=8* 2\\\\=16`

Number of math problems solve at the beginning of the 9th minute is given by
`30-16=14`

Answer 2

14

Explanation:

If he is solving 2 problems per minute and 8 minutes have passed, he has solved

2*8 = 16 problems

There are 30 problems and he has solved 16

30-16 = 14

There are 14 problems left to solve at the start of the 9th minute