Q5 of 26 Page 103

A pump of 5 HP can lift 36000 litres of water in 8 hours. Let’s work out using the method of the Rule of Three how long it will take to lift 63000 litres of water by a 7 HP pump.

formula:-


theorem1:-


The Rule of Three is a Mathematical Rule that allows you to solve problems based on proportions. By having three numbers: a, b, c,


(a)Direct proportions rule of 3:-


if ab


c then


(b)inverse proportions rule of 3:-


if ab


c then


(i)direct method----


(ii)indirect or inverse proportions xy=k



given:-method used is called indirect or inverse proportions method



w1=5,w2=7,l1=36000,l2=63000,h1=8,h2=?





h2=6.4 hr


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