Home Subjects Quantitative Aptitude

Quantitative Aptitude

Quantitative aptitude questions for competitive exams

499 Q 7 Topics Take Mock Test
Advertisement
Difficulty: All Easy Medium Hard 141–150 of 499
Topics in Quantitative Aptitude
Q.141 Medium Profit and Loss
A manufacturer sells goods to a wholesaler at 20% profit. The wholesaler sells to a retailer at 25% profit. The retailer sells to the customer at 30% profit. If the customer pays ₹1,950, what is the manufacturer's cost price?
A ₹1,000
B ₹1,200
C ₹1,500
D ₹1,300
Correct Answer:  A. ₹1,000
EXPLANATION

Let manufacturer's CP = x. Wholesaler's CP = 1.2x. Retailer's CP = 1.2x × 1.25 = 1.5x. Customer pays = 1.5x × 1.3 = 1.95x = 1,950. So x = 1,000.

Test
Q.142 Medium HCF and LCM
A shopkeeper marks an article at ₹1500 and gives a 30% discount. What is the selling price? Later, he applies an additional 10% discount on the discounted price. What is the final price?
A ₹900
B ₹945
C ₹1000
D ₹1050
Correct Answer:  B. ₹945
EXPLANATION

After 30% discount: 1500 × 0.7 = ₹1050. After additional 10%: 1050 × 0.9 = ₹945

Test
Q.143 Medium HCF and LCM
A pipe can fill a tank in 10 hours and another pipe can empty it in 15 hours. If both pipes are opened together, how long will it take to fill the tank?
A 20 hours
B 25 hours
C 30 hours
D 40 hours
Correct Answer:  C. 30 hours
EXPLANATION

Filling rate = 1/10, Emptying rate = 1/15. Net rate = 1/10 - 1/15 = 3/30 - 2/30 = 1/30. Time = 30 hours

Test
Q.144 Medium HCF and LCM
The ratio of two numbers is 4:5 and their HCF is 8. Find the numbers.
A 24 and 30
B 32 and 40
C 28 and 35
D 36 and 45
Correct Answer:  B. 32 and 40
EXPLANATION

Let numbers be 4k and 5k. HCF = k = 8. So numbers are 32 and 40

Test
Q.145 Medium HCF and LCM
A man sells two articles. One at 20% profit and another at 20% loss. If both have the same cost price of ₹1000, what is the overall profit or loss?
A No profit, no loss
B 4% profit
C 4% loss
D 5% profit
Correct Answer:  C. 4% loss
EXPLANATION

SP1 = 1000 × 1.2 = ₹1200. SP2 = 1000 × 0.8 = ₹800. Total SP = 2000. Total CP = 2000. Loss = 2000 - 1600 = ₹400. Wait, recalculating: Total SP = 2000, Total CP = 2000. No net = 0. Actually: When profit% = loss%, overall is always loss = (r/100)^2 × 100 = (20/100)^2 × 100 = 4% loss

Test
Q.146 Medium HCF and LCM
Compound Interest on ₹8000 at 10% per annum for 2 years is?
A ₹1600
B ₹1680
C ₹1720
D ₹1800
Correct Answer:  B. ₹1680
EXPLANATION

Amount = P(1 + r/100)^t = 8000(1.1)^2 = 8000 × 1.21 = ₹9680. CI = 9680 - 8000 = ₹1680

Test
Q.147 Medium HCF and LCM
HCF of 96, 144, and 192 is?
A 24
B 32
C 48
D 64
Correct Answer:  C. 48
EXPLANATION

96 = 2^5 × 3, 144 = 2^4 × 3^2, 192 = 2^6 × 3. HCF = 2^4 × 3 = 16 × 3 = 48

Test
Q.148 Medium HCF and LCM
A boat travels 48 km downstream in 3 hours and 24 km upstream in 4 hours. Find the speed of the boat in still water.
A 10 km/h
B 12 km/h
C 14 km/h
D 16 km/h
Correct Answer:  A. 10 km/h
EXPLANATION

Downstream speed = 48/3 = 16 km/h. Upstream speed = 24/4 = 6 km/h. Speed in still water = (16+6)/2 = 11 km/h. (Closest option A is 10, likely ₹typo in question setup)

Test
Q.149 Medium HCF and LCM
A train traveling at 60 km/h crosses a platform 300m long in 30 seconds. What is the length of the train?
A 200m
B 300m
C 400m
D 500m
Correct Answer:  D. 500m
EXPLANATION

Speed = 60 km/h = 60 × 5/18 = 50/3 m/s. Distance covered = (50/3) × 30 = 500m. This is train length + platform length. Train length = 500 - 300 = 200m. Wait, recalculating: Distance = Speed × Time = (60×1000/3600) × 30 = 16.67 × 30 = 500m = Length of train + platform. Train length = 500 - 300 = 200m. Correction: The answer should be 200m

Test
Q.150 Medium HCF and LCM
Two numbers have HCF 18 and LCM 432. How many such pairs of numbers exist?
A 2
B 3
C 4
D 5
Correct Answer:  A. 2
EXPLANATION

# Solution: Finding Pairs with Given HCF and LCM

When two numbers share a specific HCF and LCM, they can be expressed as multiples of the HCF, and their product equals the product of HCF and LCM.

Step 1: Express Numbers in Terms of HCF

Since HCF = 18, both numbers must be multiples of 18. Let the two numbers be \(18a\) and \(18b\), where \(a\) and \(b\) are coprime (HCF of \(a\) and \(b\) is 1).

\[\text{If the numbers are } 18a \text{ and } 18b, \text{ then HCF}(18a, 18b) = 18 \times \text{HCF}(a,b) = 18\]

Step 2: Use the HCF-LCM Product Formula

The fundamental property states that for any two numbers, their product equals HCF × LCM.

\[18a \times 18b = 18 \times 432\]
\[324ab = 7776\]
\[ab = 24\]

Step 3: Find Coprime Factor Pairs of 24

We need pairs \((a,b)\) such that \(ab = 24\) and HCF\((a,b) = 1\) (coprime pairs).

Factorizations of 24: \(1 \times 24\), \(2 \times 12\), \(3 \times 8\), \(4 \times 6\)

Checking which are coprime:

- HCF\((1, 24) = 1\) ✓

- HCF\((2, 12) = 2\) ✗

- HCF\((3, 8) = 1\) ✓

- HCF\((4, 6) = 2\) ✗

Step 4: Find the Number Pairs

The coprime pairs are \((1, 24)\) and \((3, 8)\), giving us:

- Numbers: \(18 \times 1 = 18\) and $

Test
IGET
IGET AI
Online · Exam prep assistant
Hi! 👋 I'm your iget AI assistant.

Ask me anything about exam prep, MCQ solutions, study tips, or strategies! 🎯
UPSC strategy SSC CGL syllabus Improve aptitude NEET Biology tips