Word Problems
Mental Math
Problem Solving
100
Lindsey’s e-mail account was bombarded with 34,000 spam messages. The web interface allows Lindsey to delete batches of 50 messages at one time, a process that takes 0.5 second to complete. What is the fewest number of minutes will it take Lindsey to delete all 34,000 messages if she deletes batches of 50 messages at a time? Express your answer to the nearest whole number.
What is 6
100
On a number line, what is the nearest integer to pi squared?
10
100
Emilio started a job on July 1, 2000 at a salary of $40,000. If he got an increase of 10% each year, in what year did his salary first exceed $80,000?
What is 2008
200
Enoch has a photo that is 8 inches high and 6 inches wide. He wants to enlarge it so that it can fit into a frame that is 10 inches by 7 inches. How much will he need to crop from the width to exactly fill the entire frame? Express your answer as a decimal to the nearest tenth.
What is 0.5
200
If a − b = 0, what is the value of a ×b? Express your answer in terms of a.
What is a x a or a squared
200
If the mean of the integers 7, 3, 11, 13, 5 and x is 4 more than the mode of the six integers, what is the value of x?
3
300
At 1:00 p.m. an airplane left the local airport and flew due east at 300 mi/h. At 3:00 p.m. a second plane left the same airport and flew due north at 400 mi/h. Assuming the curvature of the earth is negligible, how many miles apart are the planes at 8:00 p.m.?
What is 2900 miles
300
What is the product of the greatest common factor and least common multiple of 48 and 72?
What is 3456
300
After 6 new students entered the Happy Hearts Childcare Center and 2 students exited, there were 3 times as many students as before. How many students were present before students entered and exited the center?
What is 2
400
A bus stopped at Main Street and boarded passengers, after which half of its seats were filled. At its next stop, at Oak Street, 2 passengers got off and 7 got on, and then 60% of the seats were filled. How many seats are there on the bus?
What is 50
400
The denominator of a fraction is 2 more than its numerator. The reciprocal of this fraction is equal to the fraction itself. What is the sum of its numerator and denominator?
What is 0
400
In a school that has 20 teachers, 10 teach mathematics, 8 teach social studies and 6 teach science. Two teach both mathematics and social studies, but none teach both social studies and science. How many teach both mathematics and science?
What is 2
500
Elisa had a new fishbowl but no fish, so Kendell gave her half of his goldfish. Elisa’s fishbowl was not very large, so she gave half of her new goldfish to Rocky. Rocky kept 8 of the goldfish he was given and gave the remaining 10 goldfish to Aster. What is the difference between Kendell’s starting number of goldfish and the number of goldfish Elisa kept for her new fishbowl?
What is 54 goldfish
500
A mother was 26 years old when her daughter was born. The mother is now 6 years less than 3 times as old as her daughter. How old is the daughter now?
What is 16
500
By the time Shana had completed 3/8 of her first lap in a race, she had also completed 1/32 of the entire race. How many laps were there in the race?
What is 12 laps
M
e
n
u