Answer :
20% of 150 are done
0.2 * 150 = 30
150 - 30 are remaining
120 are remaining
0.2 * 150 = 30
150 - 30 are remaining
120 are remaining
R= left papers. r=150-20%×150=150-0.2×150=0.8×150=120
There are 120 papers left.