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.

1. 600 tiles

2. $120

3. 50.3cm2

Step-by-step 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

step-by-step explanation:

answers available in this download

(pearson%2c%25202012)%2520bbs.pdf& usg=aovvaw1obmtxnfghfgxhx0urh_je

let x and 400 - x be the two numbers.  

==> 0.80x + 0.85(400 - x) = 400 - 68 from the statement of the problem.  

< ==> 0.80x + 0.85(400 - x) = 400 - 68  

==> 340 - 0.05x = 332  

< ==> -0.05x = -8 ==> x = 160, the first number ==> 400 - x = 240, the second number.