The volume of the rectangular prism shown is 60 cm.
What is the value of ?
, 2017
Pick one
Solution
The denominators of the two fractions are 7 and 63.
Since , then we must also multiply the numerator 3 by 9 so that the fractions are equivalent. That is, . Therefore, the number that goes into the so that the statement true is 27.

Want a route through all this instead of an archive? The track
puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.