Mother 13

The mother brought 4 1/8 kg of meat. She used 1 1/3 kg to cook and care for her family and 3/4 kg to make beef steak. How many kilograms of meat were left?

Correct answer:

m =  2 ¹⁄₂₄ = 49/24 kg

Step-by-step explanation:

$$\begin{gathered} a=4\frac{1}{8}=4+\frac{1}{8}=\frac{4\cdot 8+1}{8}=\frac{32+1}{8}=\frac{33}{8}=4.125\text{kg} \\ b=1\frac{1}{3}=1+\frac{1}{3}=\frac{1\cdot 3+1}{3}=\frac{3+1}{3}=\frac{4}{3}\doteq 1.3333\text{kg} \\ c=\frac{3}{4}=0.75\text{kg} \\ s=b+c=\frac{4}{3}+\frac{3}{4}=\frac{16}{12}+\frac{9}{12}=\frac{16+9}{12}=\frac{25}{12}\doteq 2.0833\text{kg} \\ m=a-s=\frac{33}{8}-\frac{25}{12}=\frac{99}{24}-\frac{50}{24}=\frac{99-50}{24}=\frac{49}{24}=\frac{49}{24}\text{kg}=2\frac{1}{24}\text{kg}=2.0417\text{kg} \end{gathered}$$

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