Three grades of rice costing ₹40, ₹55 and ₹70 per kg are mixed in the ratio $2 : 3 : 5$ by weight. What is the cost per kg of the mixture?

₹50.50Correct answerYour answer₹55Correct answerYour answer₹59.50Correct answerYour answer₹62.50Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

Take 2 kg, 3 kg and 5 kg: cost = $2 \times 40 + 3 \times 55 + 5 \times 70 = 80 + 165 + 350$ = ₹595.
Weight = 10 kg.
Cost per kg = ₹59.50.

Worth noting

₹55 is the unweighted average of the three prices; ₹50.50 applies the ratio in reverse order $(5 : 3 : 2)$ .

Ten questions from Averages, at your own pace.

Three grades of rice costing ₹40, ₹55 and ₹70 per kg are mixed in the ratio 2:3:52 : 3 : 52:3:5 by weight. What is the cost per kg of the mixture?