+37146 Before you can add or subtrac numbers with fractions involved you have to have a COMMON DENOMINATOR.
The denoms in this problem are 21 and 7 21 is an easy common denom for these tww.....right?
22 2/21 = ((22 x 21) + 2 ) / 21 = 464/21 8 1/7 = ( (8x21) + (3x1) ) / 21 = 171/21
Now we can do the math: 464/21 - 171/21 = (464-171)/21 = 293/21 you can simplify this to 13 20/21
