Some rice

Rose had some rice. She gave 1/4 of it to her sister and cooked 1/6 of the remaining. What fraction of the rice did she cook?
b. If she cooked 1⁄2 kg of rice, how much rice did she have at first?

Correct answer:

a =  1/8
b =  4 kg

Step-by-step explanation:

$a=\frac{1}{6}\cdot (1-\frac{1}{4})=\frac{1}{8}=0.125$

$$\begin{gathered} a\cdot b=\frac{1}{2} \\ 0.125\cdot b=\frac{1}{2} \\ 0.125\cdot b=1/2 \\ 0.25b=1 \\ b=\frac{1}{0.25}=4 \\ b=4=4\text{kg} \end{gathered}$$

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