Question

Teena's calculator is broken and does not have key 9 that works! With this broken calculator she found out the value of (-35) x 99. Explain your reasoning carefully and clearly

Answer 1

(-35) * (100 - 1)

Explanation:

She was able to find the value of (-35) * 99 without using the missing 9 button on her calculator.

The easiest way to do this is to replace 99 with another set of numbers that has the same value as 99.

(100 - 1) has the same value as 99. So, Teena can replace 99 with (100 - 1):

(-35) * (100 - 1)

It will yield the desired result.