1. Sonam subtracted two unknown decimal numbers and got a difference of 0.762, so the two original numbers must add up to that difference. 2. Dorji ran 15.75 km in 2 hours while Wangchuk ran 12.90 km in the same time period. Dorji ran 2.85 km more than Wangchuk. Together they ran a total of 15.75 + 12.90 = 28.65 km. 3. When Lhamo was 9 years old she was 1.234 m tall, and after 5 years she was 1.65 m tall. So in that time she grew 1.65 - 1.234 = 0.416 m.