Answer:
3700 x 2 = 7400 plus 1233.333... ≈ 8633
Step-by-step explanation:
Since the money (3700) doubles every 6 years we know that we multiply it by 2 (6 years times 2 = 12 years) but we still have 2 years. 2 years of 6 years = 1/3 more. 1/3 of 3700 ≈ 1233. Add 1233 to 7400 to get 8633, the answer.