Which country added the most gold to its reserves in

Find the simplified value of the given expression:

(12 ÷ 3 of 2 + 11 of 2) ÷ 4

Simplify the following expression:

    (400 +175) ² - (400 – 175) ² / (400 × 175)

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

?² - 22² = 900 ÷ 4 - √1089

Simplify: 0.004 × 0.5

420 ÷ 7 + 140 % of 20 + ? × 13 = 18 × 15

150% of ? + 280 ÷ 35 = 13² - 12² + 7

756 + 432 – 361 + ? = 990

15848 ÷ 4 – 793 × 6 + 3628 = 3 × ?

What value should come in the place of (?) in the following questions?

√16 * ? = √144 + (18 * 4 ÷ 3)

√0.49 + √6.25 + √1.44 + √1.21 =? % of 125