John mows 40% in 20 minutes, how much more time does he need?

30 more mins.because 40 percent in 20 mins=80 percent in 40 mins
and the 20 percent left is the same thing as 40/2 so then you also have to do 20mins/2=10

8 mins because 40 percent of 20 equals 8
So the answer is 8 minutes

I'll do the first one for you. it isn't very hard at all.on number one, you have (50 × 3), which equals 150, and (3 × 3), which equals 9. after you establish that, you add 150 and 9 together. so, (150 + 9) equals 159.this means that 53 × 3 = 159.