Explanation

Let's use the inverse proportion:

30 workers × 20 days = x workers × 40 days

x = (30 × 20) / 40

x = 15

Explanation

Convert minutes to seconds:

5 minutes = 5 × 60 = 300 seconds

Ratio = 300 seconds : 180 seconds

= 5:3

Explanation

Explanation

1 hour = 60 minutes

Ratio = 60 minutes : 300 minutes

= 1 : 5

Explanation

Total age = 20 × 3 = 60 years

Ratio = 2:5:8

Sum of ratios = 2+5+8 = 15

Oldest student's age = (8/15) × 60 = 32 years

Explanation

Given ratio: 50 paisa:1 rupee:2 rupee = 2:5:8

Let's assume the number of coins of each denomination are:

50 paisa = 2x

1 rupee = 5x

2 rupee = 8x

Total amount = Rs. 352

The value of coins is:

50 paisa coins = 2x * 0.50 = Rs. x

1 rupee coins = 5x * 1.00 = Rs. 5x

2 rupee coins = 8x * 2.00 = Rs. 16x

Adding these values, we get:

x + 5x + 16x = 352

Combine like terms:

22x = 352

Divide by 22:

x = 16

Now, find the total number of coins:

50 paisa coins = 2x = 2(16) = 32

1 rupee coins = 5x = 5(16) = 80

2 rupee coins = 8x = 8(16) = 128

Total number of coins = 32 + 80 + 128 = 240

So, the correct answer is: 240

Explanation

Let the numbers be 6x and 5x.

6x - 5x = 6

x = 6

Numbers are:

6x = 6 × 6 = 36

5x = 5 × 6 = 30

Explanation

Let the numbers be 5x and 4x.

Given:

5x - 4x = 8

x = 8

Numbers are:

5x = 5(8) = 40

4x = 4(8) = 32

Explanation

Divide both numbers by their greatest common divisor (GCD), which is 4:  

36 ÷ 4 = 9  

80 ÷ 4 = 20

Explanation

Let's convert both measurements to the same unit (inches):

5 feet = 5 × 12 = 60 inches

3 inches = 3 inches

Now, the ratio = 60 : 3 → simplify by dividing both sides by 3 → 20 : 1