The phrase "increased by 20 percent" basically means to take 20% of the given number, which is 200, and add it to 200. You're basically asked to find 120% of 200.
If we were to convert 120% to fraction form, would you agree that it becomes 6/5? Because in order to do that, you have to divide the 120 by 100 and put that as the numerator, and 1 as the denominator.
120%
= (120/100)/1
= 1.2/1 <--- We can't leave decimals in fractions, so we have to multiply the decimal to give us a whole number. In this case, you had to multiply 5 to 1.2 to give you a whole number of 6. But when you do that, as a rule of fractions, you're required to multiply the denominator by 5 as well.
= (1.2 * 5)/(1 * 5)
= 6/5
Now we have 120% in fraction form. From this point on, you can just easily multiply it by 200 to give you the answer.
(6/5) * 200
= (6 * 200)/5
= 1200/5
Which simplifies to:
240.
