Answer:
a=55
Explanation:
This question is asking for you to find the whole (a), given a part (11). This can be done through multiplication. 20% is 1/5 of 100%. This means to find the whole number, you should multiply the part by 5. 11*5=55. So, a must equal 55.
We can check this answer by working backward. Do this by finding 20% of 55, and checking to see if it is 11. To find a percentage of a number, multiply that number by the percent in decimal form. So, 20% of 55 is equal to 0.2*55, which is 11. Therefore, the answer is correct.