MCQ
If $4, a, a, 36$ are in proportion, then $a =$
- A$24$
- ✓$12$
- C$3$
- D$24$
✓
Answer
Correct option: B.
$12$
$4, a, a, 36$ are in proportion; therefore, we get:
$4 : a : : a : 36$
$\Rightarrow 4 : a = a : 36$
$\Rightarrow 4 \times 36 = a \times a$
$\Rightarrow 144 = a2$
$\Rightarrow a = 12$
$4 : a : : a : 36$
$\Rightarrow 4 : a = a : 36$
$\Rightarrow 4 \times 36 = a \times a$
$\Rightarrow 144 = a2$
$\Rightarrow a = 12$
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