Question

63 is 150% of

Answer 1

Set up an equation usiing what we know:
\[63=1.5x\]and solve for x:\[x=\frac{63}{1.5}\]\[x=42\]

Answer 2

And of course you can check it by going the other way:\[42*1.50=?\]\[42*1.5=63\] So it checks.