Nate starts his camping trip with 70 matches. He drops 10 in a creek and his dog eats twice as many. How many matches does he have left? Let's answer step by step:
First find the number of matches the dog eats: 10 matches * 2 = 20 matches. Then subtract all the lost matches from the starting number to find the final number: 70 matches - 10 matches - 20 matches = 40 matches. The answer: 40.