76.  $\frac{75}{?}=\frac{?}{147}$

77.  13.8 × 16.7 × 21.4 – 2931.844 =?

78.  10531 + 4813 – 728 =? × 87

79.  (4.6 × 2.8 × 5.5) – (3.2 × 4.5 × 2.8) =?

80.  $\frac{3}{5}$ of $25 \%$ of $740=?$

81.  $(51)^{3} \times(14)^{3}-(19077)^{2}=?$

82.  $\frac{6.4 \times 8.5 \times 2.5}{3.2 \times 12.5}=?$

83.  $8 \frac{5}{6} \div 10 \frac{11}{36}=?$

84.  43% of 583 - ? % of 401 = 158.46

85.  $\sqrt{?}+24=\sqrt{2209}$

86.  $101120 \div \sqrt{?}=316 \times 5$

87.  If $(12)^{3}$ is subtracted from the square of a number the answer so obtained is 976. What is the number?

88.  $\frac{3}{4}$ of $\frac{5}{6}$ of $\frac{7}{10}$ of $1664=?$

89.  $441 \div 3 \times \sqrt{?}=10290$

90.  $\left[(12)^{2}+(6)^{2}\right] \div(?)^{2}=7.2$