(0.49) 4 x (0.343) 4 ÷ (0.2401) 4 = (70 ÷ 100) ? + 3

(0.49) 4 x (0.343) 4 ÷ (0.2401) 4 = (70 ÷ 100) ? + 3

Explanation

(0.7) ^? + 3 = (0.49 x 0.343/0.2401)^4

(0.7)^? + 3 = (0.7)^4

On comparing the exponents both sides, we get

? + 3 = 4

∴ ? = 4 - 3 = 1