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Question
Find the fourth proportional to 1.5, 2.5, 4.5
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Solution
Let fourth proportional to 1.5, 2.5, 4.5 be x
then 1.5 : 2.5 : : 4.5 : x
∴ 1.5 × x = 2.5 x 4.5
x = `(2.5 xx 4.5)/(1.5)`
= 7.5.
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