Question

what should be added to 7 4/15 to get 18

Answer 1

hye

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let the number be x 

7 4/15 =  109 /15 


we have to find What should be added to105/15 to get 18

so lets form an equation

=> x + 105 / 15 = 18

=> x = 18 - 105/15

=> x =  270 /15 - 105/15

=> x =  165/15

=>  x =11


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hope it helps

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Answer 2

Let the number which is to be added to 7 4/15 to get 18 be x
Therefore
7 4/15 + x =18
109/15 + x = 18
(109 + 15x)/15 = 18
109 + 15x = 270
15x = 270 - 109
15x = 161

x = 161/15

x = 13 1/15