Subject
Quantitative Aptitude
Topic
Percentage
In the expression ab2, the values of both variables a and b are decreased by 20%. By this, the value of the expression is decreased by
In the expression ab2, the values of both variables a and b are decreased by 20%. By this, the value of the expression is decreased by
ক)
40%খ)
80%গ)
48.8%ঘ)
51.2%ঙ)
52.3%Explanation
The given expression is ab2. Given that, value of both expression is decreased by 20%, then On decreasing a by 20% ⇒ new a = a – a × (20/100) = a – (a/5) = 4a/5 Similarly, new b = 4b/5 So now, expression ab2 will become Change in the value of expression = new expression – old expression ⇒ Change in the value of expression = % decrease in the given expression = (change in expression)/(old expression) × 100 % decrease in the given expressionRelated questions
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