ANSWERS
Find out the how many weeks will it take for Mary and Joe to have the same amount saved.
To proof
Let us assume that the number of week take for Mary and Joe to have the same amount saved be x.
As given
Mary start with $10 and earns $10 each week mowing lawn.
Joe already has $20 from birthday gifts and earns five dollars a week pulling weeds.
than the equation
10 + 10x = 20 +5x
5x = 10
x = 2 weeks
therefore 2 weeks will it take for Mary and Joe to have the same amount saved.
Hence proved