You have to go past the decimal point in since the first number in the tenths place is a zero you can't really round here so you go to the hundreds place and not so three you round down because 3 is closer to 0 then it is 10 so it would be 1. 4
The percent decrease is 20%.
150 - 120 = 30
30 divided by 150 = 0.2
0.2 as a percent is 20
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