MCQ
$(3^{-1}\times5^{-1})^{-1}=$
- A$\frac{1}{15}$
- B$-\frac{1}{15}$
- ✓$15$
- D$-15$
✓
Answer
Correct option: C.
$15$
$(3^{-1}\times5^{-1})^{-1}$
$=\Big(\frac{1}{3}\times\frac{1}{5}\Big)^{-1}$ $\Big(\text{As},\text{x}^{-1}=\frac{1}{\text{x}}\Big)$
$=\Big(\frac{1}{15}\Big)^{-1}$
$=\frac{15}{1}$ $\Big(\text{As},\text{x}^{-1}=\frac{1}{\text{x}}\Big)$
$=15$
Hence, the correct alternative is option $(c).$
$=\Big(\frac{1}{3}\times\frac{1}{5}\Big)^{-1}$ $\Big(\text{As},\text{x}^{-1}=\frac{1}{\text{x}}\Big)$
$=\Big(\frac{1}{15}\Big)^{-1}$
$=\frac{15}{1}$ $\Big(\text{As},\text{x}^{-1}=\frac{1}{\text{x}}\Big)$
$=15$
Hence, the correct alternative is option $(c).$
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