Question

5 years ago, Lucky would be thrice as old as Lovely. 10 years later, Lucky will ne twice as old as Lovely. How old are they now? Answer using 1 variable ( i.e. 'x' ) only.


Class 8​

Answer 1

Answer:

Step-by-step explanation:

Age of lovely=X

Lucky=3x

After 10yrs,,

Lovely=10+X

Lucky=3x+10-----------(1)

ATQ,,

lucky=2(10+X)-----------(2)

Equating (1)&(2)

3x+10=2(10+X(

3x+10=20+2x

X=10

Answer 2

• Let present age of Lucky be (x) years and present age of Lovely be (y) years.

» Five years ago, Lucky would be thrice as old as Lovely.

A.T.Q.

⇒ (x - 5) = 3(y - 5)

⇒ x - 5 = 3y - 15

⇒ x - 3y = - 15 + 5

⇒ x - 3y = - 10

⇒ x = 3y - 10 _________ (eq 1)

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» Ten years later, Lucky will ne twice as old as Lovely.

A.T.Q.

⇒ (x + 10) = 2(y + 10)

⇒ x + 10 = 2y + 20

⇒ x - 2y = 20 - 10

⇒ x - 2y = 10

⇒ 3y - 10 - 2y = 10 [From (eq 1)]

⇒ y - 10 = 10

⇒ y = 20 (age of Lovely)

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Put value of y in (eq 1)

⇒ x = 3(20) - 10

⇒ x = 60 - 10

⇒ x = 50 (age of Lucky)

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Present age of Lucky = 50 years

Present age of Lovely = 20 years

_______ [ ANSWER ]

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✡ VERIFICATION :

From above calculations we have x = 50 and y = 20

Put them in this equation : x = 3y - 10

→ 50 = 3(20) - 10

→ 50 = 50

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