Use the formula the inverse square law if you need it to help

III. For the following problems, work out the new mAs and give a new mA and time in decimal form that will give you the desired mAs. Remember that it is not always possible to get the exact mAs with the mA and time combinations available on your x-ray equipment. Choose an mA and time that are reasonable for your equipment. Original New Distance Time Distance Time (in) MA (sec) mAs (in) MA (sec) 1. 72 300 0.15 60 2. 48 800 0.07 44