A car travels 560 km in 9.5 hours, partly at 40 km/h and partly at 160 km/h. Find the distance travelled at 160 km/h.
240 km
Let t hours be spent at 160 km/h, so \((9.5-t)\) hours at 40 km/h.
\(40(9.5-t)+160t = 560\).
\(380-40t+160t=560 \Rightarrow 120t=180 \Rightarrow t=1.5\).
Distance at 160 km/h: \(160\times1.5=240\) km.
Hence, the distance travelled at 160 km/h is 240 km.
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