Question 50

Two numbers a and b are inversely proportional to each other. If a increases by 100%, then b decreases by:

Inverse proportionality is expressed as follows : 

$$a\propto \frac{1}{b}$$

$$\Rightarrow$$ a*b = constant 

When value of a changes, the value of b changes accordingly such that their product remains same.

Thus, new value of a $$a^{'} = a + a = 2a $$

Thus, the new value of b $$b^{'}$$ can be solved by : 

$$a^{'}*b^{'}=a*b$$

$$\Rightarrow 2a*b^{'}= a*b $$

$$\Rightarrow b^{'}= \frac{b}{2} $$

Thus b decreases by 50%. 

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