If 80% of 90 is greater than 70% of a number by 30, what is the number?  Choose one
A) 70  B) 60  C) 10  D) 75  E) 85
Explanation:   80/100 * 90 - 70/100 * x = 30   72 - 70/100 * x = 30   72 - 30 = 70/100 *x   42 = 70/100 * x     42 * 100 / 70= 
<gadget id="calculator">  42 * 100 / 70</gadget>
<output>60</output>
x   60= x   Answer: Option 60
<result>B</result>
If 80% of 90 is greater than 70% of a number by 30, what is the number?