7)  5 + 1/8 [-] 2 -  1/4
     5 - 2 which equals to 3 
     1/8 - 1/4 = _____
      Now, 1/8 - 2/8 = negative -1/8
        Therefore, your answer for this question would have to be : 2 7/8
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8) 7 1/3 = 22/3 
    18 5/6 = 113/6
     7 3/8 = 59/8
         {for the mixed number just multiply and add} 
        Therefore your answer might be: 33 13/14 
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10) 35(400) 
      35 ÷ 100
              = .35
       .35(400)
          Therefore , your answer would have to. be 140 
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Good day ☺