A boy rides bike at an average speed of 15km/hour, how long will it take him to ride 40km?

Use the knowledge of x- and y- intercepts to choose the correct graph of the equation 3x+6y=6

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At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?