Zber zeleniny

Covina nazbieral 6 4/5 kg fazule, 3 ¼ kg reďkovky a 9 5/8 kg paradajok. Koľko kg zeleniny dokopy nazbierala?

Správna odpoveď:

x =  19 ²⁷⁄₄₀ = 787/40 kg

Postup správneho riešenia:

$$\begin{gathered} b=6\frac{4}{5}=6+\frac{4}{5}=\frac{6\cdot 5+4}{5}=\frac{30+4}{5}=\frac{34}{5}=6,8\text{kg} \\ r=3\frac{1}{4}=3+\frac{1}{4}=\frac{3\cdot 4+1}{4}=\frac{12+1}{4}=\frac{13}{4}=3,25\text{kg} \\ t=9\frac{5}{8}=9+\frac{5}{8}=\frac{9\cdot 8+5}{8}=\frac{72+5}{8}=\frac{77}{8}=9,625\text{kg} \\ x=b+r+t=\frac{34}{5}+\frac{13}{4}+\frac{77}{8}=\frac{272}{40}+\frac{130}{40}+\frac{385}{40}=\frac{272+130+385}{40}=\frac{787}{40}=\frac{787}{40}\text{kg}=19\frac{27}{40}\text{kg}=19,675\text{kg} \end{gathered}$$

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