Mixture of 40% Ryegrass and 25% Ryegrass is 30% Ryegrasssimba12123 wrote:Seed mixture x is 40 percent ryegrass and 60 percent bluegrass by weight, seed mixture y is 25 percent ryegrass and 75 percent fescue. If a mixture of x and y contains 30 percent ryegrass. WHat percent of the weight of the mixture is x?
a. 10 %
b.33.3%
c.40%
d.50%
e.66.67%
qa is b
although the answer explanation is nice in the back of the og 11 book, I am looking for a faster and less algebraic approach. ANy help?
If Mixture of 40% Ryegrass and 25% Ryegrass were (40+25)/2 = 32.5% Ryegrass then both would have been equal in quantity
But Since Mixture of 40% Ryegrass and 25% Ryegrass is 30% Ryegrass so it's more influenced by 25% Ryegrass and therefore
40------(40-30)=10-------30------(30-25)=5-------25
i.e. the ratio must be 10:5 = 2:1 = y : x
i.e. x = (1/3)*100 = 33.33%
Answer: Option B