1、An ant covers a distance of 90 metres in 3 hours. The average speed of the ant in decimetres per minute is____.
2、In a certain town some people were affected by a ’flu’ epidemic. In the first month 20% of the population contracted the flu whilst 80% were healthy.
In the following month 20% of the sick people recovered and 20% of the
healthy people contracted the disease.
What fraction of the population is healthy at the end of the second month?
3、Mpho, Barry, Sipho, Erica and Fatima are sitting on a park bench.
Mpho is not sitting on the far right. Barry is not sitting on the far left.
Sipho is not sitting at either end. Erica is sitting to the right of Barry,
but not necessarily next to him. Fatima is not sitting next to Sipho.
Sipho is not sitting next to Barry.
Who is sitting at the far right?
4、Of the 28 T–shirts in a drawer, six are red, five are blue, and the rest are white. If Bob selects T–shirts at random whilst packing for a holiday, what is the least number he must remove from the drawer to be sure that he has three T–shirts of the same colour?