Arlene

Arlene weighs 55.8 kg. Tina is two times heavier than Arlene. Together with Karen, the three of them weigh 210.09 kg. How many kilograms does Karen weigh?

Correct answer:

K =  42.69 kg

Step-by-step explanation:

$$\begin{gathered} A=55.8\text{kg} \\ T=2\cdot A=2\cdot 55.8=\frac{558}{5}=111.6\text{kg} \\ s=210.09\text{kg} \\ s=T+A+K \\ K=s-T-A=210.09-111.6-55.8=42.69\text{kg} \end{gathered}$$

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