# Oracle SAT Math Problem Explanation!

### Explanation and Tips!

**To solve this problem quickly, pick real dimensions for the rectangle. Let’s say the rectangle is 10 by 10. That makes the original area of the rectangle 100. **

**According to the problem if we increase the length by 10% and decrease the width by s percent, the new area will be decreased by 12%. This means the new area would be 88.**

**Our length of 10 is increased by 10%, so it will now equal 11.**

**So really, the question is asking what dimension, when multiplied by 11, is equal to 88? Or even better, 88 divided by 11 is what?**

**Keep in mind that for the width, we need to decrease 10 by s percent. So for answer choice A, 10 decreased by 12% would be 8.8. For answer choice B, 10 decreased by 15% would be 8.5.**

**Test each answer choice until you find the dimension s that gives you an area of 88. **

**The answer is C! A length of 11 and width of 8 will give you a total area of 88!**

**Two quick tips from this problem:**

**To decrease 100 by 12%, you can either****A) find 12% of 100 and then subtract that from 100 or B) find 88% of 100. B) saves you time and a calculation!****Picking real values to work with will help the accuracy of your work. The algebraic equation for solving this question looks like this:**

**.88(xy) = (1.1x (1-. s)y)**

**...and coming up with this much less solving it is time consuming and very prone to error. Instead, plug in values!**