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Rational Numbers — MATHS STD 7 — Question

ICSE BoardEnglish MediumSTD 7MATHSRational Numbers5 Marks
Question
Evaluate: $\frac{-3}{8}+\frac{-5}{12}$
✓

Answer

$\frac{-3}{8}+\frac{-5}{12}$
28,12
24,6
22,3
31,3
1,1

L.C.M. of 8 and $12=2 \times 2 \times 2 \times 3=24$
$ \Rightarrow \frac{-3 \times 3}{8 \times 3}+\frac{-5 \times 2}{12 \times 2} $
$(\because$ L.C.M. of 8 and $12=24)$
$ \Rightarrow \frac{-9-10}{24}=-\frac{19}{24} $

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