b. 24 mm
use the pythagorean theorem.
a^2 + b^2 = c^2
a^2 + 7^2 = 25^2
a^2 + 49 = 625
a^2 = 576
a = 24
answer: b. 24 mm
total cost for tiles and paints is $924.
we have been given that a community hall is in the shape of a cuboid. the hall is 40m long 15m high and 3m wide.
the paint will be required for 4 walls and ceiling.
let us find area of walls and ceiling.
therefore, the area of walls and ceiling is 1410 square meters.
given: cost for 10 litre of paint is $10 and 10 litre paint covers 25 square meter. therefore,
therefore, the total painting cost is $564.
tiles will be required for floor. let us find the area of floor.
given: 1m squared floor tiles costs $3. so,
therefore, the total tiles cost is $360.
now let us find combined total cost of tiles and paint.
therefore, the combined total cost of tiles and paint is $924.