Question

The cost of 1 kg of potato is ₹60. 1 kg of onions costs 10% less than 1 kg of potato. If I pay ₹ 180 for potatoes, then what will be the cost of onions? (weight of an onion is same as that of the potatoes)

• A. ₹160
• B. ₹162
• C. ₹172
• D. ₹170

Answer 1

The correct option is B ₹162

The cost of 1 kg potato = ₹60
The cost of 1 kg onion is 10% less than 1 kg of potato.
$\frac{10}{100}\times 60=6$
$\Rightarrow$ 60 - 6 = ₹54
Therefore, cost of 1 kg onion = ₹54

Now, the cost of potatoes is directly proportional to the weight of potatoes

$\frac{Costofpotatoes}{Weightofpotatoes}=constant$

$\frac{60}{1}=\frac{180}{x}$

Hence, weight of potatoes
$=\frac{180}{60}=3kg$

The weight of onions and potatoes are equal.
Cost of 1 kg onion = ₹54
Therefore, cost of 3kg onions = 3 x 54 = ₹ 162.