Answer :
Final answer:
Harriet can make 4 tonnes of concrete.
Explanation:
A fraction is a mathematical representation of a part of a whole, expressed as the ratio of two numbers. The top number called the numerator, represents the part being considered, while the bottom number, the denominator, indicates the total number of equal parts in the whole.
To determine how much concrete Harriet can make, we need to find the ratio of sand to concrete.
Given that it takes tonnes of sand to make a tonne of concrete, the ratio is 1:1.
Therefore, Harriet can make 4 tonnes of concrete.
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