Math CentralQuandaries & Queries


Question from Ron, a parent:

The number of dollars that Tracy has in her pocket is an odd number.
Hal gave Tracy $\$2$ more than she already had in her pocket.
The number of dollars Tracy now has cannot be _________.
a) $\$60$ b) $\$62$ c) $\$64$ d) $\$68$

Hi Ron,

Think of the situation this way. Hal has $\$2$ more than Tracy so he gives Tracy $\$1$ and now they both have the same amount. Tracy started with an odd number of dollars so they each have an even number of dollars. Hal now gives his money to Tracy so the number of dollars she has is twice an even number. What do you know about twice an even number?


About Math Central


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.
Quandaries & Queries page Home page University of Regina PIMS