EXERCISE 4 (OBJECTIVE TYPE QUESTIONS SOLUTION IN 21 30)

21.       Given exp. = 18 – [5 –{6 + 2 ( 7 – 3)}] = 18 –[5 –{6 + 2 x 4}]

=18 –[5 – {6 + 8}] = 18 – [5 – 14] = 18 – {- 9] = 18 + 9 = 27.

22.       Given exp. = 1 ÷[ 1 + 1 ÷{ 1 + 1 ÷( 1 + 1/2)}] = 1 ÷ [ 1 + 1 ÷ { 1 + 1 ÷3/2}]

= 1 ÷ [ 1 + 1 ÷ { 1 + 1 x 2/3}] = 1÷ [ 1 + 1 ÷{1 + 2/3}]

= 1 ÷ [ 1 + 1 ÷ 5/3] = 1 ÷ [ 1 + 1 x 3/5] = 1÷[1 + 3/5] = 1÷ 8/5 = 1x 5/8 = 5/8.

23.       Given exp. = 8 – [ 5 –(-1)] ÷ 2 / |2| - | -3| ÷ 3 8-[5 + 1]÷2/2-1 =8 – 3 = 5.

24.       5/3 + 3//4 = 20 + 9/12 = 29/12 = 2 5/12 <5; 7/3 + 11/5 = 35 + 33/15 = 68/15 =4 8/15 <5;

11/4 + 8/3 = 33 + 32/12 = 65/12 = 5 5/12 < 5; 13/5 + 11/6 = 78 + 55/30 = 133/30 = 4 8/15 <5.

25.       Given exp. = 28 + 14 + 7 +4 + 2 + 1 / 28 = 56 /28 = 2.

26.       Given exp. = 7/4 + 16 / 3 + 17/5 = 105 + 320 + 204 / 60 = 629 / 60 = 10  29/60.

27.       Given exp. 41/2 + 91/3  - 91/6 =(123+ 182/6) – 91/6 = 305 / 6 – 91/6 =214 /6 = 107/3 = 35  2/3

28.       Given exp. =-1 + 4 + 2 =6.

29.       Given exp. = 1/(7/3) + 1/(7/4) = 3/7 + 4/7 =7/7 =1.

30.   Let 35/6 – 35/9 – x=1.

Then, X = 35 / 6 – 35 /9 -1 =35 /6 –( 35/9 + 1) = 35/6 – 44/9 = 105 -88/18 = 17 /18.