A school has 8 periods a day each of 45 minutes of duration. How long would each period be, if the school has 9 periods a day assuming the number of school hours to be the same?
Solution:
Consider x to be the number of periods and y as the duration of each period.
Let x₁ = 8, y₁ = 45, x₂ = 9, y₂ = ?
If the number of period increase, then the duration of per period will decrease. So, it is inverse variation.
Two numbers x and y are said to be in inverse proportion when an increase in one quantity decreases the other quantity and vice versa.
xy = k or x = (1/y) k
where k is a constant.
Hence, x₁y₁ = x₂y₂
8 × 45 = 9 × y₂
y₂ = (8 × 45)/9
y₂ = 40
Thus, each period would be 40 minutes long.
☛ Check: NCERT Solutions for Class 8 Maths Chapter 13
Video Solution:
A school has 8 periods a day each of 45 minutes of duration. How long would each period be, if the school has 9 periods a day assuming the number of school hours to be the same?
NCERT Solutions Class 8 Maths Chapter 13 Exercise 13.2 Question 11
Summary:
A school has 8 periods a day each of 45 minutes of duration. If the school has 9 periods a day assuming the number of school hours to be the same, each period would be 40 minutes long.
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