The price of 80 apples is equal to that of 120 oranges. The price of 60 apples and 75 oranges together is Rs. 1320. The total price of 25 apples and 40 oranges is:
Answer: B
Let price of one apple \(=a\)
price of one orange \(=b\)
Price of 80 apples = Price of 120 oranges
\(\Rightarrow 80a=120b\\ \Rightarrow 2a=3b\\ \Rightarrow b = \dfrac{2a}{3}~\cdots(1)\)
Price of 60 apples + Price of 75 oranges =Rs. 1320
\(\Rightarrow 60a+75b=1320\\ \Rightarrow 4a+5b=88\\ \Rightarrow 4a+\dfrac{5(2a)}{3}=88 \quad \text{[ Because substituted value of } b \text{ from }(1)]\\ \Rightarrow 12a+10a=88 \times 3\\ \Rightarrow 6a+5a=44 \times 3\\ \Rightarrow 11a=44 \times 3\\ \Rightarrow a=4 \times 3=12\)
\(b=\dfrac{2a}{3}=\dfrac{2 \times 12}{3}=8\)
Total price of 25 apples and 40 oranges
\(=25a+40b\\=25\times12+40\times8\\=300+320\\=620\)