Judy studied for 7/12 hours and her sister studied for 2/3 of a hour about how much time did they studied all together

So you first need to make both equivalent fractions. You do that by making the denominator the same so you need to find a common multiple between both which is 12 so you multiply 2/3 by 4 on the top and bottom to get something equivalent to 7/12. 7/12 +8/12=15/12 now you divide 15 and 12 to have it in fraction mode you’ll be getting that Judy and her sister studied for 1 hour and 25 minutes