The value of the lesser integer is 28
Answer:
(a). $20,000
(b). The estimate will be lower than the actual amount.
Step-by-step explanation:
We have been given that Michael saves $423 dollars a month for college.
(a). We know that 1 year equals 12 months.
4 years = 4*12 months = 48 months.

Since we are asked to find the estimated amount of money Michael will save in 4 years, so we will estimate both quantities as:



Therefore, Michael will save approximately $20,000 in 4 years.
(b).
The estimate will be lower than the actual amount as we rounded $423 down $23 to nearest hundred that is $400 and rounded 48 up 2 to nearest ten that is 40.
Therefore, the estimate will be lower than the actual amount.
You multiply the number outside the parenthesis with both of the numbers in the parenthesis separately.