# Problem of the Week 05-16-16

May 18, 2016 | Waterford Lakes

Lower Elementary:
Question: Ellie breaks open her piggy bank and finds the coins below. How much money does Ellie have?

Solution:  Ellie has 1 half dollar worth 50¢, 2 quarters worth 25¢ each, 2 dimes worth 10¢ each, 1 nickel worth 5¢, and 2 pennies worth 1¢ each. So, Ellie has 50¢ + 25¢ + 25¢ + 10¢ + 10¢ + 5¢ + 1¢ + 1¢ = 127¢.  Since there are 100¢ in a dollar, that means Ellie has \$1 and 27¢, or \$1.27.

Upper Elementary:
Question: Packs of trading cards cost \$3.50. How many packs of trading cards can Max buy with a \$20 bill?

Solution:  First, let’s estimate how many packs of cards Max can buy by rounding. \$3.50 rounds up to \$4.00, and \$4.00 goes into \$20.00 five times. Let’s try it with the actual value of a pack of cards; \$3.50, five times is \$17.50. That means that if Max buys 5 packs, he’ll have \$2.50 left, which isn’t enough to buy another pack of cards. So, Max can buy 5 packs of cards at most.

Middle School:
Question: Harrison bought a box of 64 colored pencils for \$24.00 and a box of 36 crayons for \$12.60. Which cost more, a single colored pencil or a single crayon?