Question

6 adults and 4 senior citizens have to pay $228 while 13 adults and 7 senior citizens have to pay $459 to visit an exhibition at the ArtScience museum. Find the total amount 2 adults and a senior citizen have to pay to visit the exhibition​

Answer 1

Answer: Rs. 69

Step-by-step explanation:

Let the amount that the adults have to pay be Rs. “x” and the amount that the senior citizens have to pay be Rs. “y”.

Step 1:

According to the question, we get

Equation 1:

6x + 4y = 228  

Equation 2:

13x + 7y = 459  

Step 2:

Then, by multiplying equation 1 by 7 & equation 2 by 4, we get

7 * [6x + 4y = 228]

⇒ 42x + 28y = 1596 …. (iii)  

And,

4 * [13x + 7y = 459]

⇒ 52x + 28y = 1836 …. (iv)

Step 3:

Now, Subtracting eq. (iii) from eq. (iv), we get

52x + 28y = 1836

42x + 28y = 1596

(-)    (-)         (-)

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10 x = 240

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⇒ x = 240/10 = 24

Substituting value of x in eq. (1)

(6*24) + 4y = 228  

⇒ y = [228 - 144]/4 = 21

Step 4:

Thus,  

The total amount that 2 adults and a senior citizen have to pay to visit the exhibition is,

= 2x + y

= (2*24) + 21 ….. [substituting x= 24 & y = 21]

= Rs. 69