Quantitative Aptitude - MCQ Practice Questions

SP = 900 is 90% of CP. So CP = $\frac{900}{0}$.9 = 1000. For 15% profit, SP = 1000 × 1.15 = 1150.

In 12 hours, clock gains 5 minutes. In 24 hours, it gains 10 minutes. So at 12 PM Tuesday, clock will show 12:10 PM.

Let milk = 5x, water = 3x. After adding 8 liters water: 5x/(3x+8) = $\frac{5}{4}$. 20x = 15x + 40. 5x = 40. x = 8. Milk = 40 liters.

Combined rate = $\frac{1}{10}$, A's rate = $\frac{1}{15}$. B's rate = $\frac{1}{10}$ - $\frac{1}{15}$ = $\frac{1}{30}$. B needs 30 days

SP = 500, Discount = 10%, MP × 0.90 = 500, MP = $\frac{500}{0}$.90 = ₹555.56

Speed = $\frac{150}{6}$ = 25 m/s = 25 × $\frac{18}{5}$ = 90 km/h

Profit ratio = 20000:30000 = 2:3. Q's share = 5000 × $\frac{3}{5}$ = ₹3000

If $\frac{1}{3}$ tank takes 4 hours, full tank takes 4 × 3 = 12 hours

SP = 2000 × (1 - 0.15) = 2000 × 0.85 = ₹1700

Relative speed = 40 + 50 = 90 km/h. Distance = 90 × 2 = 180 km

Amount = 10000(1.10)² = 10000 × 1.21 = ₹12100. CI = 12100 - 10000 = ₹2100

When multiple workers complete a task at different rates, their combined work rate equals the sum of individual rates. The combined rate is found by adding the reciprocals of individual completion times.

Step 1: Find individual work rates

Work rate is the fraction of work completed per day. If A completes work in 8 days, B in 12 days, and C in 16 days:

Step 2: Find combined work rate

When working together, rates add:

Step 3: Find common denominator and add

The LCM of 8, 12, and 16 is 48:

Step 4: Calculate time to complete work

If combined rate is $\frac{13}{48}$ per day, then time to complete 1 full work is:

**Answer: They can complete the work together in $\frac{48}{13}$ days or approximately 3.69 days (Option D)**

Monthly savings = 50000 × (1-0.60) = ₹20,000. Annual = 20,000 × 12 = ₹240,000

New income = Original × 1.25. 62,500 = Original × 1.25. Original = 62,$\frac{500}{1}$.25 = ₹50,000

Total distance = 200 + 100 = 300 m. Speed = 54 km/h = 15 m/s. Time = $\frac{300}{15}$ = 20 seconds

Total distance = 5×3 + 4×2 = 15 + 8 = 23 km. Total time = 5 hours. Avg speed = $\frac{23}{5}$ = 4.6 km/h

After 20% discount = 1000 × 0.80 = ₹800. After 10% discount = 800 × 0.90 = ₹720

Let A, B, C complete work in a, b, c days respectively. 1/a + 1/b = $\frac{1}{12}$, 1/b + 1/c = $\frac{1}{15}$, 1/a + 1/c = $\frac{1}{20}$. Adding all three: 2(1/a + 1/b + 1/c) = $\frac{1}{12}$ + $\frac{1}{15}$ + $\frac{1}{20}$ = $\frac{12}{60}$ = $\frac{1}{5}$. So 1/a + 1/b + 1/c = $\frac{1}{10}$. Therefore, 1/a = $\frac{1}{10}$ - $\frac{1}{15}$ = $\frac{1}{30}$. A completes work in 30 days.