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If x : y − 5 : 4 and 2 : x = 3 : 8, find the value of y. - Mathematics

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प्रश्न

If x : y − 5 : 4 and 2 : x = 3 : 8, find the value of y.

योग

उत्तर

x : y = 5 : 4

and 2 : x = 3 : 8

Then, `"x"/"y" = 5/4`  ...(i)

and `2/"x" = 3/8`   ...(ii)

`"x" = (2 xx 8)/3 = 16/3`

Now put the value of x in eq. (i)

`"x"/"y" = 5/4`

y = x `xx 4/5`

y = `16/3 xx 4/5 = 64/15`

The value of y is `64/15`​ or approximately 4.27.

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अध्याय 6: Ratio and Proportion (Including Sharing in a Ratio) - Exercise 6 (B)

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सेलिना Concise Mathematics [English] Class 7 ICSE
अध्याय 6 Ratio and Proportion (Including Sharing in a Ratio)
Exercise 6 (B) | Q 6

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