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The variable x varies directly as y and x = 80 when y is 160. What is y when x is 64? - Mathematics

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प्रश्न

The variable x varies directly as y and x = 80 when y is 160. What is y when x is 64?

योग
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उत्तर

If x varies directly as y.

∴ `x/y = k` (constant)   ...(i)

If x = 80 and y = 160

∴ `x/y = 80/160 = 1/2`

⇒ `k = 1/2`

When x = 64, then from equation (i),

`64/y = 1/2`  ...[Putting the value of k]

⇒ y = 64 × 2 = 128

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

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 8
अध्याय 10 Direct and Inverse Proportions
Exercise | Q 64. | पृष्ठ ३२२

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