Question

what is to be added to -21/5 to get a sum of 15/4​

Answer 1

Question :

what is to be added to -21/5 to get a sum of 15/4 ?

Answer :

Let x be added to -21/5 to get a sum of 15/4 .

Now ,

$x + ( \frac{ - 21}{5} ) = \frac{15}{4} \\ x = \frac{15}{4} + \frac{21}{5} \\ x = \frac{ \: 15 \times 5 + 21 \times 4\: \: }{20} \\ x = \frac{75 + 84}{20} \\ x = \frac{159}{20}$

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Hope it helps !!