Level 3 25% of the people are performers for a concert and the rest are spectators. 60% of the spectators are adults and there are 420 less child spectators than adult spectators. How many adult spectators must join so that 56% of the people are adult spectators?
Level 3
A rectangular tank, 80 cm by 50 cm by 40 cm, is filled with water to a height of 5 cm. The ratio of the volume of water in the tank to that in a pail is 5: 2. If 23 of the pail is filled with water, find
the volume of the pail.
the minimum number of such pails to fill the tank.
Level 3
Wilfred saves 10% of his allowance. When his allowance was increased by 20%, his savings rose proportionately to $180. What was his original allowance?
Level 3
Half an hour ago, 50% of the people at a circus were females. 42 females and 2 males left afterwards. The remaining people were then told to form groups of 5. In each group, there were 3 males. How many people were there at the circus in the end?
Level 3
The average height of a group of boys was 143 cm. After 6 girls with a total of 948 cm joined the group, the average height of all the children increased to 146 cm.
