Answer:
1.2c
Step-by-step explanation:
increasing by a percent means you find the percent of the original, then add it to the original.
so if 10 increases by 20% that means 20% of 10 is 2 so you add that to 10 so now it is 12.
you can write this out as x + x*.2 = x(1 + .2) = 1.2x.
So you just add 1 and the decimal form of the percent and multiply x by it. in your case you have c though so the result is 1.2c
