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If x varies inversely as y and y = 60 when x = 1.5. Find x. when y = 4.5.

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प्रश्न

If x varies inversely as y and y = 60 when x = 1.5. Find x. when y = 4.5.

योग
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उत्तर

If x varies inversely as y.

∴ xy = k (constant)  ...(i)

If x = 1.5 and y = 60

∴ xy = 1.5 × 60 = 90

⇒ k = 90

When y = 4.5, then from equation (i),

4.5 × y = k

⇒ 4.5 × y = 90  ...[Putting the value of k]

⇒ `y = 90/4.5 = 20`

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अध्याय 10: Direct and Inverse Proportions - Exercise [पृष्ठ ३२२]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 8
अध्याय 10 Direct and Inverse Proportions
Exercise | Q 66. | पृष्ठ ३२२

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