Q121 of 147 Page 8

What’s the Error? Reeta evaluated – 4 + d for d = –6 and gave an answer of 2. What might Reeta have done wrong?

Let us solve the expression for Reeta.

We have, -4 + d for d = -6


Put d = -6 in -4 + d.


-4 + d = -4 – 6


⇒ -4 + d = -10


The answer is coming out to be -10, while Reeta gave an answer of 2.


She must have subtracted 4 from 6, replacing -4 from 4.


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