Find the common difference using the first two terms.<br><br>&bull; 6600 − 6200 = 400<br>&bull; The pattern increases by 400 each step.<br>&bull; First blank: 6600 + 400 = 7000<br>&bull; Check: 7000 + 400 = 7400 ✓<br>&bull; Second blank: 7400 + 400 = 7800<br><br>Final Answer: 7000, 7800