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तमिलनाडु बोर्ड ऑफ सेकेंडरी एज्युकेशनएसएसएलसी (अंग्रेजी माध्यम) कक्षा ७

It takes 120 minutes to weed a garden with 6 gardeners. If the same work is to be done in 30 minutes, how many more gardeners are needed?

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प्रश्न

It takes 120 minutes to weed a garden with 6 gardeners. If the same work is to be done in 30 minutes, how many more gardeners are needed?

योग
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उत्तर

Let the, number of gardeners needed be x.

Number of gardeners 6 x
Time in minutes 120 30

As the number of gardeners increases the time decreases.

They are in inverse proportion,

x1y1 = x2y

6 × 120 = x × 30

x = `(6 xx 120)/30`

x = 24

∴ To complete the work in 30 min gardeners needed = 24

Already existing gardeners = 6

∴ More gardeners needed = 24 – 6 = 18

18 more gardeners are needed

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Direct and Inverse Proportion - Exercise 4.2 [पृष्ठ ८०]

APPEARS IN

सामाचीर कलवी Mathematics - Term 1 [English] Class 7 TN Board
अध्याय 4 Direct and Inverse Proportion
Exercise 4.2 | Q 7 | पृष्ठ ८०

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