Homework

Together, the mother and Kate weigh 21.9 kg more than the father. The father weighs 8.1 kg more than the mother. The father weighs 40.2 kg more than Kate. Determine the weights of the father, mother, and Kate.

Final Answer:

o =  70.2 kg
m =  62.1 kg
k =  30 kg

Step-by-step explanation:

$$\begin{gathered} m+k=o+21.9 \\ o=m+8.1 \\ o=k+40.2 \\ (o-8.1)+k=o+21.9 \\ o=k+40.2 \\ k=30 \\ k-o=-40.2 \\ Row2-Row1\to Row2 \\ -o=-70.2 \\ o=\frac{-70.2}{-1}=70.2 \\ o=\frac{351}{5}=70.2=70.2\text{kg} \end{gathered}$$

$m=o-8.1=70.2-8.1=62.1\text{kg}$

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