A students first reduced a number by 20% and then increased it again by 20% . If the difference between the last number and the original number is 8, then the original number was :

35% of Tahia's income is equal to 25% of Nona's income . The ratio of Tahia's income to Noria's income is :

A watch which gains 5 seconds in 3 minutes was set right at 7am . In the afternoon of the same day when the tr...

Which of these numbers are least like the others : 3, 5, 11, 14, 17, 21.

Insert the missing number : 16, 33, 67, 135, 271, (...)

The numbers 13,7 and 11 would enjoy the company of which of these numbers : 10, 15, 17, 12, 18 ?

Lamp A is less bright than Lamp B; Lamp B is less brighter than Lamp C; Lamp C is as bright as Lamp D. Lamp B...