A group of 80 students took a statistics exam and the following scores were recorded:

68 84 75 82 68 90 62 88 76 93 73 79 88 73 58 93 71 59 58 51 61 65 75 87 74 62 95 78 63 72 66 96 79 65 74 77 95 85 78 86 71 78 78 62 80 67 69 83 76 62 71 75 82 89 67 58 73 74 73 65 81 76 72 75 92 97 57 63 68 83 81 82 53 85 94 52 78 88 77 71

Calculate:

Variance and standard deviation from a grouped distribution with the lowest score interval limits of 50-54. (compute to two decimal places)

Variance:

Standard Deviation: