Explanation : Using student activities and interacts classroom question would be most effective in helping the students to understand. The students will perform activities related to the functioning of the eyes (persistence of vision etc.), study the model of the eye and discuss among themselves, ask questions to satisfy their queries
Explanation : Let the fraction be 5x/7y
Now, sum of numerator and denominator = 91
i.e 5x + 8y = 91 => 13x = 91 => x = 7
∴ Numerator = 35 and denominator = 56
:. Difference of denominator and numerator = 56 - 35 = 21