Mr. Sharma goes to the market with Rs. 252 but we don’t know if he spends the entire amount in buying watermelons and mangoes.
If he bought x mangoes and y watermelons.
Then, 4x + 3y ≤ 252
∴ We cannot determine the amount he spent in buying mangoes.
Hence, option 5.
Extra Learning:
If the question would have given that, Mr. Sharma spent the entire amount in buying watermelons and mangoes then the question would have the following solution.
Let the number of mangoes he buys be x and the number of water melons he buys be y.
Then, 4x + 3y = 252
x = (252 – 3y)/4
The possible values of y such that x is a natural number (he has to buy at least one mango and one watermelon) are given in the following sets:
(x, y) = (60, 4), (57, 8), (54, 12), (51, 16), (48, 20), (45, 24), (42, 28), (39, 32), (36, 36), (33, 40), (30, 44), (27, 48), (24, 52), (21, 56), (18, 60), (15, 64), (12, 68), (9, 72), (6, 76), (3, 80)
We can see that the values of y are multiples of 4 in ascending order and values of x are multiples of 3 in descending order.
But, the number of watermelons and mangoes are not co prime to each other, number of mangoes is multiples of 4 and the difference between the number of mangoes and watermelons should be minimum. We get two possible values of x and y, respectively 48 and 20 and 24 and 52.
∴ The amount he spends on mangoes, in this case too, cannot be determined.
