If the numerical value of the area of a circle is seven

What value should come in place of (?) in the given expression.

450 ÷ 9 + 75% of 160 − 64 ÷ 4 = ?

2/5 of 3/4 of 7/9 of 14400 = ?

7/3 of 4/5 of 15/56 of ? = 83

[564 + 32 of 18 × 9 ÷ 12 + 16² ] ÷ 4 = ?

What should come in place of (?) question mark in the given expression.

 (25% of 320) + (3/8 of 400) − 30 = ?

45% of 360 - 160 + ? = √324

187 ÷ 5 ÷ 0.4 = ? – 24 × 2.4

Find the simplified value of the following expression:

[{12 + (13 × 4 ÷ 2 ÷ 2) × 5 – 8} + 13 of 8]

18 × 15 + 86 – 58 =? + 38

√(24²+285-8²-172) = ?²