Question
An alloy contains 50% iron, 30% zinc, and 20% aluminum. How
much iron should be added to 30 kg of the alloy so that the new alloy contains 60% iron?Solution
ATQ,
Quantity of the alloy = 30 kg
Quantity of iron in 30 kg alloy = (0.50 × 30) = 15 kg
Quantity of zinc in 30 kg alloy = (0.30 × 30) = 9 kg
Quantity of aluminum in 30 kg alloy = (0.20 × 30) = 6 kg
Let the quantity of iron to be added be x kg.
According to the question,
Quantity of iron in the new alloy = (Quantity of zinc + Quantity of aluminum)
(15 + x) = (9 + 6)
Or, x = 15 - 15 = 0
No iron needs to be added as it already satisfies the condition.
24.99 × 32.05 + ? - 27.01 × 19.97 = 29.99 × 27.98
(14.56)² × √840 =?
...- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exactvalue.)
24.99% of 1619.78 + (1259.84 ÷ 12.24) = ? × 16.98
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
56.02% of 1499.98 + 64.04% of 2501.01 = ? + 25.05 × 49.98 + 6.063
- 27.99² - 40.02% of 419.99 + √3135.99 = ? X 5.99
The speed of the boat in still water is 20% less than the speed of the boat in downstream. The time taken by the boat to cover 780 km distance in upstre...
[(5/6 of 720.21) + 39.79% of 550.14] × (√120.91 + 29.99% of 200.09) = ?
? = 21.91% of (36.2 × (144.01 + 5.95)) + 16.71
