Twenty years ago, the father's age was 4 times the age of his son, 4 years hence the father's age  2 times the age of his son. Find the present age of the father and the son.

A train has length of 150 meters. It is passing a man who is moving at 2 km/hour in the same direction of the train, in 3 seconds. Find out the speed of the train?

Lisa gives her little brother Sam a 15-second (sec) head start in a 300-meter (m) race. During the race. Sam runs at an average speed of 5 m/sec and Lisa runs at an average speed of 8 m/sec, not including the head start. Since the time Lisa started running, what is the best approximates the number of seconds that had passed when Lisa caught up to Sam?

A typical image taken by Peter's camera is 15 megabytes in size. Peter can upload photos at a rate of 7 kilo bits per second for a maximum of 5 hours per day. If I megabit equals 1024 kilobites, what is the maximum number of images Peter can upload each day?

Susan invited 13 of her friends for her birthday party and created return gift hampers. comprising one each of $3, S4, and $5 gift certificates. One of her friends did not turn up and Susan decided to rework her gift hampers such that each of the 12 friends who turned up got $13 worth gift certificates. How many gift hampers did not contain $5 gift certificates in the new configuration?

What is the least number that when divided by 44 leaves a remainder 31, when divided by 56 leaves a remainder 43 and when divided by 32 leaves a remainder 19?