Answer:
5 17/18
Explanation:
Your calculator can help with this.
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The integer parts of the mixed numbers can be dealt with separately. The fractional parts are added and subtracted using a common denominator. Here, that denominator is the least common multiple (LCM) of 2, 3, and 9, so is 18.
((7 2/3) -(4 8/9)) +((5 2/3)) -(2 1/2))
= (7 2/3) +(5 2/3) -((4 8/9) +(2 1/2))
= 12 4/3 -(6 +8/9 +1/2)
= 13 6/18 -(6 +16/18 +9/18)
= 13 6/18 -(6 +25/18) = 13 6/18 -(7 7/18)
= (13 -7) +(6/18 -7/18)
= 6 -1/18
= 5 17/18
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Additional comment
Doing the math in the manner shown above means you can mostly do it without a calculator. If you like, you can convert all of the numbers to improper fractions, then add those. This often requires a calculator.
= (138/18 -88/18) +(102/18 -45/18)
= 50/18 +57/18
= 107/18 = 5 17/18