Explanation

To find 25% of 150, multiply 150 by 0.25:

150 × 0.25 = 37.5.

Therefore, 37.5 is 25% of 150.

Explanation

100 is 20% of 500. 

Explanation

Let the number be x.  

40% of x = 380  

⇒ (40/100) × x = 380  

⇒ 0.4x = 380  

⇒ x = 380 ÷ 0.4  

⇒ x = 950

Explanation

Let the number be x.  

25% of x = 20  

⇒ (25/100) × x = 20  

⇒ x = 20 × (100/25)  

⇒ x = 80

Explanation

Discount = 15% of 80

= 0.15 * 80

= 12

Sale price = Original price - Discount

= 80 - 12

= 68

Explanation

Step 1: Multiply the number of students in each class by their pass percentage

- Class 1: 10 students × 20% = 2 passed  

- Class 2: 20 students × 30% = 6 passed  

- Class 3: 30 students × 60% = 18 passed  

- Class 4: 40 students × 100% = 40 passed  

Step 2: Add total passed students and total students

- Total passed = 2 + 6 + 18 + 40 = 66  

- Total students = 10 + 20 + 30 + 40 = 100

Step 3: Calculate the overall percentage

Pass % = (66 / 100) × 100 = 66%

Explanation

15% of 1000 =  

(15 ÷ 100) × 1000 = 0.15 × 1000 = 150

Explanation

15% of 200 =

(15 ÷ 100) × 200 = 0.15 × 200 = 30

Explanation

Let total salary = S

1. Spends 1/3 on personal affairs → Remaining = (2/3)S  

2. Gives half of remaining to wife → Remaining after this = (1/2) × (2/3)S = (1/3)S  

3. Invests 75% of final remaining → Invested = 75% of (1/3)S = (3/4) × (1/3)S = (1/4)S  

   So final amount left after investing = Remaining - Invested = (1/3)S - (1/4)S = (4/12 - 3/12)S = (1/12)S

Given this final amount = 1000  

So, (1/12)S = 1000  

=> S = 1000 × 12 = 12,000

Explanation

Let the first part be x, lent at 10% for 8 years.  

So, interest = (x × 10 × 8)/100 = 0.8x

Let the second part be (4200 − x), lent at 7% for 5 years.  

So, interest = [(4200 − x) × 7 × 5]/100 = (35/100)(4200 − x) = 0.35(4200 − x)

Since both interests are equal:

0.8x = 0.35(4200 − x)

Solve:

0.8x = 1470 − 0.35x  

0.8x + 0.35x = 1470  

1.15x = 1470  

x = 1278.26

So, second part = 4200 − 1278.26 = Rs. 2,921.74 ≈ Rs. 2,921