math
posted by mar .
A group of goats&duck s hav a total of 99 heads n legs among thm. Ther r twice as many ducks as ther r goats. How many r ther of ech?

let the number of goats be x
then the number of ducks is 2x
goats:
number of heads = x
number of legs = 4x
ducks:
number of heads 2x
number of legs = 22x) = 4x
x+4x + 2x+4x 99
11x = 99
x = 9
9 goats, 18 ducks