5321135
A chocolate bar is divided into equal pieces, as shown. The orange-shaded pieces have already been eaten. The whole chocolate bar originally weighed \(160\,\text{g}\).
a) What fraction of the chocolate bar has been eaten? Write the fraction in simplest form.
b) What is the mass of the chocolate that has been eaten?
Hints
- Count the total number of pieces and the number of orange-shaded pieces.
- Write and simplify the fraction represented by the shaded pieces.
- To find a fraction of a quantity, divide by the denominator and multiply by the numerator.
Solution
1. The array has \(4\) rows and \(6\) columns, so there are \(4\times6=24\) pieces in all.
2. There are \(9\) orange-shaded pieces, so the fraction eaten is \(\frac{9}{24}=\frac{3}{8}\).
3. Find \(\frac{3}{8}\) of \(160\,\text{g}\): \(160\div8=20\), and \(3\times20\,\text{g}=60\,\text{g}\).
Answer
a) \(\frac{3}{8}\)
b) \(60\,\text{g}\)
