22. An Estenmeyer flask can hold

    = 0.05 ´ 4.55 liters

    = 0.2275 liters

    Number of flasks needed

    =

    = 100

    Ans : 100

23. Ð B is a right angle (Angle in a semi-circle)

         Diameter of a circle = 2 ( OA )

= 13

Using the Pythagoras theorem for D ABC,

Ð B      = right angle (angle in a semi-circle)

( BC )2 = ( AC )2 - ( AB )2

  = ( 13 )2 - ( 5 )2

  = 144

\ BC   = 12

A ( DABC)      = ½ ´ 12 ´ 5

    = 30

Ans : 120/169p

 24.         

               5 + 100 + 0.1

                   = 105.1

      Ans : 105.1

 25.         A(D DOE) = ´ Area of rectangle

OR

= ´ Area of D DKE

(DK)² = (KE)² - (DE)²

= 61² - 60²

= 121

   DK = 11

Area of a triangle = ´ 60 ´ 11

       = 330

Ans : 330

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Index

Test 3

Test 4