Question

The price of 24 apples is equal to that
of 28 oranges. The price of 45 apples and
60 oranges together is Rs. 1350. The total
price of 30 apples and 40 oranges is Rs.​

Answer 1

Answer:

900

Step-by-step explanation:

Let,

price of 1 apple=x and price of one orange=y

given,

The price of 24 apples is equal to that  of 28 oranges

=>24x = 28y         .....................eq.1

The price of 45 apples and  60 oranges together is Rs. 1350

=>45x + 60y = 1350      ......................eq.2

divide equation 1 with 4 we get,

6x = 7y    => x = 7y/6      eq.3

put eq.3 in eq.2 we get,

45(7y/6) +60y = 1350 by solving we get,

105y/2 + 60y = 1350

225y = 1350(2)

from here we get,

y = 12

putting y = 12 in eq.3 we get,

x = 14

hence,

price of 1 apple(x) = 14  and price of 1 orange(y) = 12

therefore,total price of 30 apples and 40 oranges is Rs 900

Answer 2

Solution 1

Let price of one apple = a

Price of one orange = b

Price of 80 apples = Price of 120 oranges⇒

80a = 120b

⇒2a = 3b

⇒b = 2a / 3 -------- (1)

Price of 60 apples + Price of 75 oranges = Rs. 1320

⇒60a + 75b = 1320

⇒4a + 5b = 88

⇒4a + 5 (2a)3 = 88 [∵ substituted value of b from (1)]

⇒12a + 10a = 88 × 3

⇒6a + 5a = 44 × 3

⇒11a = 44 × 3

⇒a = 4 × 3 = 12

b = 2a/3 = 2 × 12/3 = 8

Total price of 25 apples and 40 oranges

= 25a + 40b

= 25 × 12 + 40 × 8

= 300 + 320 = 620

Solution 2

80 apples ≡ 120 oranges

⇒2 apples ≡ 3 oranges

⇒60 apples ≡ 90 oranges

60 apples + 75 oranges = 1320

⇒90 oranges + 75 oranges = 1320

⇒165 oranges = 1320

⇒1 orange = 8

1 apple = 3 × 8/2 = 12

25 apples + 40 oranges

= 25 × 12 + 40 × 8 = 620