Answer:
880
Step-by-step explanation:
This problem a bit annoying, but let's classify the numbers and see where we can get from there:
Total = 10,000
Young = 3,000
Old = 7,000 (not young defined as 10,000 - 3,000)
Male = 4,600
Female = 5,400
Married = 7,000
Single = 3,000
Young Males = 1,320
Young Females = 3,000 (young) - 1,320 = 1,680
Married Males = 3,010
Married Females = 7,000 - 3,010 = 2,990
Young Married = 1,400
Young Married Males = 600
Young Married Females = 1,400 - 600 = 800
Young Female Single = ?
Young Female = 1,680 from above. But not all of them are single.
Young Married Females = 800 from above
Young Female Single = Young Female - Young Married Females = 1,680 - 800 = 880
+ 
from 30.5, which equals 