You should try this (20+7)+(10+5)=42
The formula to figure out the percentage increase or decrease is:
<span>(new - old) / old * 100% </span>
<span>new = 60 </span>
<span>old = 72 </span>
<span>(60 - 72) / 72 * 100% </span>
<span>-12 / 72 * 100% </span>
<span>= -1/6 * 100% </span>
<span>= -0.1666... * 100% </span>
<span>≈ -16.667% </span>
<span>Because it is negative, that's a decrease. </span>
<span>Answer: </span>
<span>A decrease of about 16.7%</span>
12 rainy days because 16 divided by 4 is 4. SO, 4 times 3 is 12
