Wednesday, August 7, 2013

GEOMETRY-2


Find the value of m in the following figure.





Solution

m + m + 400 = 1800

2m + 400 = 1800

2m + 400 – 400 = 1800 – 400

2m + 0 = 1400

2m = 1400

2m  = 1400
2           2

m = 700

Hence the value of m is 700   



Saturday, August 3, 2013

PERIMETER OF A SEMI-CIRCLE-1


Find perimeter of the following semi-circle



Suluhu

Perimeter = D + D
                      2

                   = ( 1122  X 70490 )    +  490
                           17          12

                   = (11 x 70 ) + 490

                   = 770 + 490

                   = 1260


Hence Perimeter is  1260 m


PERIMETER OF TRIANGLE-1



Perimeter of the following triangle is 140. Find the value of a.




Solution.

Perimeter = total of all sides

      100 = 2a + 5a + 3a

      100 = 10a

      10 100    = 110a
         110         110
 
      a = 10


Hence a is 10



ALGEBRA-4

if  11w = 25; then find w


Solution


11w = 25


11w = 25          [divide by 11 on both sides]
11       11


w = 23/11 



Hence w = 23/11  



Wednesday, July 31, 2013

PYTHAGORAS-1


Find the length  AC. [Diagram not to scale]



Suluhu

We will use the PYTHAGORAS theorem [ a2 + b2 = c2 ]

a2 + b2 = c2

AB2 + BC2 = AC2

32 + 42 = AC2

9 + 16 = AC2

25 = AC2 [Here, we find the square root of 25]

5 = AC


Hence AC = 5mm



Tuesday, July 30, 2013

CIRCLE PERIMETER-2


Find the perimeter of the circle below






Solution

Diameter = 2xr =2x70=140

So, D=140mm

Perimeter = ∏ x D


                = 22 x 14070
                    71

                = 22 x 70


                = 1540



Hence perimeter is 1540 mm. 




Monday, July 29, 2013

GEOMETRY-1


Find the value of x in the following figure



Solution

2x + 2x + 8x + 8x = 3600

4x + 16x = 3600

20x = 3600

20x   = 3600
20         20

X = 180


Hence x is 180

Saturday, July 27, 2013

ALGEBRA-3




AREA OF RECTANGLE-1

Find area of the following rectangle (diagram not to scale)




Solution

Area = Length x width

         = 38 x 20

         =760m2


Hence area is 760m2




Friday, July 26, 2013

Thursday, July 25, 2013

AREA OF CIRCULAR PRISM-1



Find area of the following circular prism which is closed on both sides




Solution

Area = 2∏rh + 2∏ x r2

=(2 x 22 x 355 x 100) + (2 x 22 x 355 x 35)
           71                                71

=(2 x 22 x 5 x 100) + (2 x 22 x 5 x 35)
                                           
=(44 x 500) + (44 x 5 x 35)

=22000+ 7700

=29700

Hence area is 29700 cm2


Wednesday, July 24, 2013

PERIMETER OF SQUARE



Perimeter of the following rectangle is 44mm. Find the value of a.




solution

Perimeter = 4 x side

44 = 4(a - 5)

44 = 4a – 20

44 + 20 = 4a

64 = 4a

64 =  4a
 4      4

16 = a

Hence a is 16     


Tuesday, July 23, 2013

SQUARE ROOTS



Find the square root of 324 by using prime factors


Solution







Hence the square root is 18

Wednesday, July 3, 2013

SQUARE PERIMETER-1

Find perimeter of the square below




Solution

Perimeter = 4  x  side

                   = 4 x 200

                   = 800


Hence perimeter is 800 mm.


Thursday, June 27, 2013

RECTANGLE PERIMETER

 Find the perimeter of the following rectangle. (diagram not to scale)



Solution

Length=60 cm, Width = 20 cm

Perimeter = 2(length + width)

                   = 2( 60 + 20)

                   =2 x 80

                   =160cm


Hence Perimeter is 160cm