Question

If 25 percent of x is 80 what is 90 percent of x

Answer 1

Method 1:

`\begin{array}{cccc}25\%&-&80&|:5\\5\%&-&16&|\cdot18\\90\%&-&288\end{array}\\\\Answer:\ 90\%\ of\ x\ is\ equal\ 288`

Method 2:

`\begin{array}{ccc}25\%&-&80\\90\%&-&a\end{array}\ \ \ |\text{cross multiply}\\\\25a=90\cdot80\ \ \ |:25\\\\a=(7200)/(25)\\\\a=288\\\\Answer:\ 288`