31. 2 x 5 = 10. Sum of decimal places = 4.
0.002 x 0.5 = 0.00010 = 0.001.
32. 1602 x 1 = 1602. Sum of decimal places = 5.
16.02 x 0.5 = 0.0010 = 0.001.
33. 14 x 14 = 196. Sum of decimal places = 6.
0.0014 x 0.001 = 0.000196.
34. 4083 x 102 x 12 = 4997592. Sum o decimal places = 5.
40.83 x 1.02 x 1.2 = 49.97592.
35. 4 x 162 = 648. Sum of decimal places = 6.
0.04 x 0.0162 ==.000648 = 6.48 x 10⁻⁴
36. 3 x 3 x 3 x 3 x 30= 2430. Sum of decimal places = 6.
3 x 0.3 x 0.03 x 0.003 x 30 = 0.002430 = 0.00243.
37. Sum of decimal places = 7.
Since the last digit to the extreme right will be zero (5 x 4 = 20), so there will be 6 significant digits to the right of the decimal point.
38. (.00625 of 23/6) = (625/100000 x 23/5) = 23/800.
39. Given product = 0.3 x 0.25 x 0.5 x 0.125 x 24
= (3.10 x 25/100 x 5/10 x 125/1000 x 24) = 9/80 = 1/8