What is it you need help with? I may be able to help.
You already know the dimensions of the original field, which is 100 yards by 60 yards ---> multiply that to get the area of the original field which is 6,000 yards square. To get the dimensions you need the area of pee-wee field which can be found by 1/4x=6,000 x is the area of the peewee field. then you figure out the dimentions from x.