# In a model of a ship, the mast is 9 cm high, while the mast of the actual ship is 12 cm high. If the length of the actual ship is 28 m, how long is the model ship?

**Solution:**

Let the length of the actual ship be x and that of the model ship be y

Actual ship |
Model ship |

12 cm | 9 cm |

28 m | ? |

More the length of the ship more would be the length of its mast. Hence, this is a direct proportion.

Two numbers x and y are said in direct proportion if, the relationship between two quantities is such that if we increase one, the other will also increase, and if we decrease one the other quantity will also decrease.

x/y = k, x = ky

where k is a constant.

Thus, x₁_{ }/ y₁ = x₂ / y₂

12 / 9 = 28 / y₂

y₂ = (28 × 9) /12

y₂ = 21 m

Thus, the length of the actual ship is 21 m.

**☛ Check: **NCERT Solutions for Class 8 Maths Chapter 13

**Video Solution:**

## In a model of a ship, the mast is 9 cm high, while the mast of the actual ship is 12 cm high. If the length of the actual ship is 28 m, how long is the model ship?

NCERT Solutions Class 8 Maths Chapter 13 Exercise 13.1 Question 6

**Summary:**

In a model of a ship, the mast is 9 cm high, while the mast of the actual ship is 12 cm high. If the length of the actual ship is 28 m, the length of the model ship is 21 m.

**☛ Related Questions:**

- Suppose 2 kg of sugar contains 9 × 106 crystals. How many sugar crystals are there in (1) 5 kg of sugar? (2) 1.2 kg of sugar?
- Rashmi has a road map with a scale of 1 cm representing 18 km. She drives on a road for 72 km. What would be her distance covered in the map?
- A 5 m 60 cm high vertical pole casts a shadow 3 m 20 cm long. Find at the same time (i) the length of the shadow cast by another pole 10 m 50 cm high (ii) the height of a pole which casts a shadow 5m long.
- A loaded truck travels 14 km in 25 minutes. If the speed remains the same, how far it travels in 5 hours?

visual curriculum