Question 14 of 22intermediate🔧 ApplyNumerical3 marks

Harmain is a 1-year-old girl. Her elder brother is 5 years old. What will be Harmain's age when the ratio of her age to her brother's age is 1:2?

Correct Answer

Given:

  • Harmain's current age = 1 year
  • Brother's current age = 5 years
  • Required ratio = 1:2

Let x = number of years from now.

Step 1: Harmain's age after x years = 1 + x

Step 2: Brother's age after x years = 5 + x

Step 3: Set up equation: (1+x)/(5+x) = 1/2

Step 4: Cross multiply: 2(1+x) = 5+x

Step 5: 2 + 2x = 5 + x

Step 6: x = 3

Answer: Harmain's age = 1 + 3 = 4 years

At that time, her brother will be 5 + 3 = 8 years old, giving ratio 4:8 = 1:2.

Exercise: Figure it Out (Section 4) | Q: 6 | (Page Page 19)
For More Understanding

Explanation

Let x years pass. Harmain's age will be (1+x) and brother's age will be (5+x). Set up the equation (1+x)/(5+x) = 1/2 and solve for x.

Solution Steps

  1. Step 1: Let x be the number of years from now.

  2. Step 2: Harmain's age after x years = 1 + x

  3. Step 3: Brother's age after x years = 5 + x

  4. Step 4: Set up equation: (1+x)/(5+x) = 1/2

  5. Step 5: Cross multiply: 2(1+x) = 5+x

  6. Step 6: 2 + 2x = 5 + x

  7. Step 7: x = 3

  8. Step 8: Harmain's age = 1 + 3 = 4 years

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