Harry is tiling a wall of area 25m squared.

A tub contains 15kg of tile cement.
The instructions say 2kg of tile cement will tile 1m squared of wall.

How many tubs does Harry need to buy?

15 kg will tile 7.5 square meters

25 / 7.5 = 3.333 = 4 tubs

15I2=7.5

25I7.5=3.333

To calculate the number of tubs Harry needs to buy, we need to find the total amount of tile cement required for the entire wall.

Given:
Area of the wall = 25 m²
Tile cement required for 1m² of wall = 2 kg

To find the total tile cement required, we can use the following formula:

Total tile cement required = Area of the wall * Tile cement required for 1m² of wall

Substituting the values:

Total tile cement required = 25 m² * 2 kg/m²
Total tile cement required = 50 kg

Now, we know that one tub contains 15 kg of tile cement.

To find the number of tubs needed, we can divide the total tile cement required by the amount of tile cement in each tub:

Number of tubs needed = Total tile cement required / Tile cement in each tub
Number of tubs needed = 50 kg / 15 kg
Number of tubs needed ≈ 3.33

Since Harry cannot purchase fractional tubs, he will need to round up to the nearest whole number. Therefore, Harry needs to buy 4 tubs of cement.

To find out how many tubs Harry needs to buy, we need to determine how many kilograms of tile cement are required for a wall of 25m².

According to the instructions, 2kg of tile cement is needed to tile 1m² of wall. Therefore, to find the total amount needed for 25m², we can multiply 2kg by 25:

2kg/m² * 25m² = 50kg

So, Harry needs a total of 50kg of tile cement for the 25m² wall.

Given that a tub contains 15kg of tile cement, we can divide the total amount needed by the amount in each tub to determine how many tubs Harry needs to buy:

50kg ÷ 15kg/tub ≈ 3.33 tubs

Rounding up, Harry needs to buy at least 4 tubs of tile cement to have enough for the entire wall.