the cost of 5 kg of suger and 7 kg of rice is 153 rs and the cost of 7 kg of sugar and 5 kg of rice is 147 rs find the cost of 6kg sugar and 10 kg of rice
Answers
i would love to solve this question using simultaenous equation, am sorry if you do not know about this method. this would give u a clue to get the ans. must be easy now u have the clue?
let one kg of sugar be y continue from here
let one kg of rice be r eliminate y
5y+7r=153 49r -25r=1071-735
7y+5r=147 24r=336
7[5y+7r=153] r=14
5[7y+5r=147] substitute to get y
35y+49r=1071 5y +7 x 14=153
35y+25r=735 5y+98=153
5y=153 -98
5y=55
y=11
Answer:
206
Step-by-step explanation:
Let’s assume the cost of 1 kg of sugar = Rs x
And, let the cost of 1 kg of rice = Rs y
Then according to the given conditions, we have
5x + 7y = 153 … (i) and
7x + 5y = 147 … (ii)
Multiplying (i) by 7 and (ii) by 5, we have
35x + 49y = 1071 … (iii)
35x + 25y = 735 … (iv)
(-)—(-)——(-)————- Subtracting (iv) from (iii), we get
24y = 336
y = 336/24
y = 14
On substituting the value of y in (i), we get
5x + 7(14) = 153
5x + 98 = 153
5x = 153 – 98
5x = 55
x = 55/5 = 11
So, the cost of 1 kg of sugar is Rs 11 and the cost of 1 kg of rice is Rs 14.
Now,
Cost of 6 kg of sugar = Rs 11 x 6 = Rs 66
Cost of 10 kg of rice = Rs 14 x 10 = Rs 140
Thus, the cost of 6 kg of sugar and 10 kg of rice = Rs 66 + Rs 140 = Rs 206.