Question

How to calculate the magnifying power of amagnifying glass 12 dioptre?

Answer 1

hey mate

here is your answer

$magnifying \: power = 1 + d \div f \\ = 1 + 25 \div 100cm \div 1 \div 12m \\ \\ = 1 + 1 \div 4 \times 12 \\ = 1 + 3 \\ = 4(answer)$

where d=least distance of distinct vision.
and f=focal length