MA DS Practice SET – 1
DS: Mixture & Alligation – Level 1
Directions: Choose the correct option (A-E) based on sufficiency.
1.
What is the ratio of milk to water in a mixture?
(1) The mixture contains 20 liters of milk.
(2) The mixture contains 30 liters of water.
(1) The mixture contains 20 liters of milk.
(2) The mixture contains 30 liters of water.
Solution (C):
To find the ratio \(M:W\), we need the quantity of both Milk and Water.
(1) Gives Milk only. Not sufficient.
(2) Gives Water only. Not sufficient.
Combined: \(M=20, W=30\). Ratio = 20:30 = 2:3. Sufficient.
2.
How many kilograms of sand are in a 50 kg concrete mix?
(1) The ratio of sand to cement is 3:2.
(2) The mixture contains only sand and cement.
(1) The ratio of sand to cement is 3:2.
(2) The mixture contains only sand and cement.
Solution (C):
(1) Gives ratio 3:2. But if there are other ingredients (like water or gravel), we can’t calculate the exact amount from just the ratio of sand to cement. Not sufficient.
(2) Confirms there are only two ingredients. But without the ratio, we don’t know the breakdown. Not sufficient.
Combined: Total = 50kg. Ratio 3:2. Only two parts. Sand = \(\frac{3}{5} \times 50 = 30\) kg. Sufficient.
3.
What is the percentage concentration of salt in a solution?
(1) The solution contains 50 grams of salt.
(2) 100 grams of water was evaporated from the solution.
(1) The solution contains 50 grams of salt.
(2) 100 grams of water was evaporated from the solution.
Solution (E):
Concentration = \(\frac{\text{Salt}}{\text{Total Solution}}\).
(1) Gives Salt mass. Total mass unknown. Not sufficient.
(2) Describes a change in the solution but gives no initial or final totals. Not sufficient.
Combined: We know Salt = 50. We know some water left. We still don’t know the **current total mass** of the solution. Not sufficient.
4.
Is the price of the mixed rice less than $5 per kg?
(1) Rice A costs $4/kg and Rice B costs $6/kg, mixed in equal amounts.
(2) Rice A costs $4/kg and Rice B costs $6/kg.
(1) Rice A costs $4/kg and Rice B costs $6/kg, mixed in equal amounts.
(2) Rice A costs $4/kg and Rice B costs $6/kg.
Solution (A):
(1) Equal amounts mean 1:1 ratio. Average price = \((4+6)/2 = 5\). Is it **less** than 5? No, it is exactly 5. We have a definite “No”. Sufficient.
(2) Doesn’t give the mixing ratio. If we use mostly A, price is near $4 (Yes). If mostly B, price is near $6 (No). Not sufficient.
5.
A tank contains a mixture of oil and water. What is the total volume?
(1) The mixture contains 40 liters of oil, which is 20% of the total.
(2) If 10 liters of water are added, the total volume becomes 210 liters.
(1) The mixture contains 40 liters of oil, which is 20% of the total.
(2) If 10 liters of water are added, the total volume becomes 210 liters.
Solution (D):
(1) \(0.20 \times V = 40 \implies V = 200\). Sufficient.
(2) \(V + 10 = 210 \implies V = 200\). Sufficient.
Score: 0 / 0