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तामिळनाडू बोर्ड ऑफ सेकेंडरी एज्युकेशनएस.एस.एल.सी. (इंग्रजी माध्यम) इयत्ता ७

If C = kd (i) what is the relation between C and d? (ii) find k when C = 30 and d = 6 (iii) find C, when d = 10 - Mathematics

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प्रश्न

If C = kd

(i) what is the relation between C and d?

(ii) find k when C = 30 and d = 6 

(iii) find C, when d = 10

बेरीज
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उत्तर

(i) Given C = kd

⇒ `"C"/"d"` = k

This is in the form `x/y` = k

As C increases d also increases

∴ It is direct proportion

(ii) When C = 30 and d = 6, k = `"C"/"d"`

= `30/6`

k = 5

(iii) When d = 6, C = 30  ...[from (ii)]

When d = 10, C = ?

`("C"_1)/("d"_1) = ("C"_2)/("d"_2)`

`30/6 = ("C"_2)/10` .......[When d = 10]

C2 = `(30 xx 10)/6`

C2 = 50

C = 50

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 4: Direct and Inverse Proportion - Exercise 4.3 [पृष्ठ ८१]

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सामाचीर कलवी Mathematics - Term 1 [English] Class 7 TN Board
पाठ 4 Direct and Inverse Proportion
Exercise 4.3 | Q 2 | पृष्ठ ८१

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