Question

Tanya paints the walls of her family room.

The room measures 3 m by 4 m by 7 m.
The walls need 2 coats of paint. A 4-L can of paint covers 40 m².
a) How much paint should Tanya buy?​

Answer 1

6.1

Explanation:

Surface area of the room = 2(lw + hl + hw)

Where,

l = length = 7 m

w = width = 4 m

h = height = 3 m

Surface area of the room = 2(lw + hl + hw)

= 2(7*4 + 3*7 + 3*4)

= 2(28 + 21 + 12)

= 2(61)

= 122 m²

A 4-L can of paint covers 40 m²

Number of 4-L can of paint needed for 1 coat = 122 m² / 40 m²

= 3.05 4-L can of paint

The walls need 2 coats of paint

Number of 4-L can of paint needed for 2 coats = Number of 4-L can of paint needed for 1 coat × 2

= 3.05 × 2

= 6.1 4-L can of paint