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तमिलनाडु बोर्ड ऑफ सेकेंडरी एज्युकेशनएसएसएलसी (अंग्रेजी माध्यम) कक्षा ७

It takes 60 days for 10 machines to dig a hole. Assuming that all machines work at the same speed, how long will it take 30 machines to dig the same hole? - Mathematics

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प्रश्न

It takes 60 days for 10 machines to dig a hole. Assuming that all machines work at the same speed, how long will it take 30 machines to dig the same hole?

योग
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उत्तर

Let the number of days required be x.

Number of machines 10 30
Number of days 60 x

As the number of machines increases it takes less days to complete the work

∴ They are in inverse proportion, x1y1 = x2y

10 × 60 = 30 × x

x = `(10 xx 60)/30`, x = 20

It takes 20 days to dig the hole

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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 4 | पृष्ठ ८०

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