Question

Form the pair of linear equations in the following problems, and find their solutions (if they exist) by the elimination method:

(i) Five years ago, Nuri was thrice as old as Sonu. Ten years later, Nuri will be twice as old as Sonu. How old are Nuri and Sonu?
(ii) lending library has a fixed charge for the first three days and an additional charge for each day thereafter. Saritha paid Rs.27 for a book kept for seven days, while Susy paid Rs.21 for the book she kept for five days. Find the fixed charge and the charge for each extra day.
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Answer 1

[HeY Mate]

Answer:

Solutions:-

(i) Let us assume, present age of Nuri is x

And present age of Sonu is y.

According to the given condition,

x – 5 = 3(y – 5)

x – 3y = -10…………………………………..(1)

Now,

x + 10 = 2(y +10)

x – 2y = 10…………………………………….(2)

Subtract eq. 1 from 2, to get,

y = 20 ………………………………………….(3)

Substituting the value of y in eq.1, we get,

x – 3.20 = -10

x – 60 = -10

x = 50

Therefore,

Age of Nuri is 50 years

Age of Sonu is 20 years.

(ii) When equation (ii) is subtracted from equation(i) we get,

2B = 6

B = 3

Substituting B = 3 in equation (i) we get,

A + 12 = 27

A = 15

Hence,

the fixed charge is Rs.15/-

And the Charge per day is Rs.3/-.

I Hope It Helps You✌️

Answer 2

Answer:

Your answer is in the attachment.

Sorry I cant answer the second one. I am really really sorry.