Problem of the Week Archive
Culinarian’s Day – July 25, 2016
Problems & Solutions
July 25th is National Culinarian’s Day. It’s a day to honor chefs and cooks or to
practice a little cooking yourself. Since we are mathematicians, let’s celebrate
by solving some food themed problems!
A cookie recipe requires 4 cups of flour to make 5 dozen cookies. If Amy needs
to make 15 dozen cookies, how many cups of flour will she need?
Fifteen dozen cookies is 3 times as many cookies as 5 dozen, so Amy will need 3 times as much flour or 3 × 4 cups =
12 cups of flour.
The math team went out to eat and ordered 7 eight-slice pizzas. What fraction of the total amount of
pizza ordered is left after 41 slices are eaten? Express your answer as a common fraction.
Severn eight-slice pizzas contain 7 × 8 = 56 slices. After 41 slices are eaten, there are 56 – 41 = 15 slices left, which is
15/56 of the total amount.
Mandy had a box of chocolate malted milk balls. She ate 5 and gave her brother 3. Then she passed
around the remaining milk balls to her 8 friends. The first friend took 1, the second friend took 3, the
third friend took 5, and so on, with each team member taking the next higher odd number of milk
balls. There were just enough milk balls in the box for the last team member to take her correct
amount. What was the original number of milk balls in Mandy’s box?
The number of milk balls Mandy started with was 5 + 3 + (1 + 3 + 5 + 7 + 9 + 11 + 13 + 15). From the eight consecutive
odd numbers, we notice four sums of 16. So, 5 + 3 + (1 + 15) + (3 + 13) + (5 + 11) + (7 + 9) = 8 + 4 × 16 = 8 + 64 =
72 milk balls.
Tito’s bill at Blue Moon Diner was $19.50 before the 6% sales tax was added. Tito wants to leave a
tip of at least 20% of the bill amount before tax is added. What is the least amount he should pay for
the bill, tax and tip?
Tito wants to pay 20% of the bill as a tip and he has to pay 6% of the bill in taxes, so he will pay an extra 26% of the bill. We
can get the total amount he will pay by multiply the bill by 1.26, which is 1.26 × $19.50 = $24.57.
Problem of the Week Archive
Culinarian’s Day – July 25, 2016
Problems
July 25th is National Culinarian’s Day. It’s a day to honor chefs and cooks or to
practice a little cooking yourself. Since we are mathematicians, let’s celebrate
by solving some food themed problems!
A cookie recipe requires 4 cups of flour to make 5 dozen cookies. If Amy needs
to make 15 dozen cookies, how many cups of flour will she need?
The math team went out to eat and ordered 7 eight-slice pizzas. What fraction of the total amount of
pizza ordered is left after 41 slices are eaten? Express your answer as a common fraction.
Mandy had a box of chocolate malted milk balls. She ate 5 and gave her brother 3. Then she passed
around the remaining milk balls to her 8 friends. The first friend took 1, the second friend took 3, the
third friend took 5, and so on, with each team member taking the next higher odd number of milk
balls. There were just enough milk balls in the box for the last team member to take her correct
amount. What was the original number of milk balls in Mandy’s box?
Tito’s bill at Blue Moon Diner was $19.50 before the 6% sales tax was added. Tito wants to leave a
tip of at least 20% of the bill amount before tax is added. What is the least amount he should pay for
the bill, tax and tip?