SMS message ratio

Jana, Petra, and Andrea sent an SMS to Superstar. The number of messages they sent was in the ratio 4:3:2, with Andrea sending 35 fewer text messages than Jan and Peter combined. How many text messages did all 3 girls send together?

Final Answer:

x =  63

Step-by-step explanation:

$$\begin{gathered} J=\frac{4}{4+3+2}\cdot x \\ P=\frac{3}{4+3+2}\cdot x \\ A=\frac{2}{4+3+2}\cdot x \\ A=J+P-35 \\ 2/9\cdot x=4/9\cdot x+3/9\cdot x-35 \\ 5x=315 \\ x=\frac{315}{5}=63 \\ x=63 \end{gathered}$$

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