Question

1. How many tiles whose length and breadth are 13 cm and 7 cm respectively are needed to cover a rectangular region whose length and breadth are 520 cm and 140 cm? 2. The length of a rectangular wooden board is thrice its width. If the width of the board is 120 cm, find the cost of framing it at the rate of $5 for 20 cm. 3. From a circular sheet of a radius 5 cm, a circle of radius 3 cm is removed. Find the area of the remaining sheet is given that π = 22 /7.

Answer 1

1. 600 tiles

2. $120

3. 50.3cm2

Explanation:

1. 520 x 140/ 13 x 7

600 tiles

2. Since length is 3 x width, length is 360.

20=5

360= 360/20= 18= 18 x 5= 90

20=5

120= 120/20= 6= 6 x 5= 30

90 + 30= 120= $120

3. 22/7 x 5 x 5= 78.5

22/7 x 3 x 3= 28.2

78.5-28.2= 50.3= 50.3cm2