So it would be x12 to the 2nd power, kinda hard to explain but i really hope this helped
Ok so if 1200 total pens and 60 were taken that's a ratio of 1200/60=20
out of 60pens 4 didn't work, again ratio is 4/60=1/15 so about 1/15 of the pens didn't work.
so we have 1200pens * 1/15broken ratio = 80 pens or we can say
20*4=80pens won't work from 20 groups of 60 and 4 out of 60 not working is 20*4=80 not working from total batch of 1200.
hope this helps you some! thank you!!!!!!!!!
9/11=x/22
11*2=22
9*2=x
x=18
9/11=18/22
Look at 36/3 = 12.
So let's try 12 along with the one before it and the one after it.
10 + 12 + 14 = 36
yay !