Xiaoxin's father was on a business trip for 7 days, and when he got home, he tore off the 7-day calendar. It is known that the sum of the numbers of the dates of these 7 days is 49. Ask Xiaoxin's father what day it is when he comes home?
小新的爸爸出差7天，当他回到家就把这7天的日历都撕下．已知这7天的日期的数字相加的和是49．问小新的爸爸回家这天是几号？
<result>10</result>