Answer:
1 : 4
Step-by-step explanation:
Let x represent the amount of 30% solution for 1 unit of 5% solution. Then the amount of acid in the mix is ...
0.30x + 0.05·1 = 0.10·(x +1)
0.30x + 0.05 = 0.10x + 0.10 . . . . eliminate parentheses
0.20x = 0.05 . . . . . . . . . . . . . . . . subtract 0.05+0.10x
x = 0.05/0.20 = 1/4
That is, the ratio x : 1 is 1 : 4.
The rules are


Let me show you why with a couple of examples: suppose we want to multiply

Since powers are just repeated multiplications, we have

Similarly, we have

Answer:
f(- 3) = - 3
Step-by-step explanation:
To evaluate f(- 3) substitute x = - 3 into f(x) , that is
f(- 3) = - (- 3)² + 6 = - 9 + 6 = - 3
150 g flour for 12 cakes
x g flour for 30 cakes
x = (150 x 30) : 12 = 375 g of flour
another method:
150 flour for 12 cakes
??? for 30 cakes
30 : 12 = 2.5
150 x 2.5 = 375 g flour
Answer:
Step-by-step explanation:
If he earns $48 dollars in 3 hours, you need to divide 48 by 3 to work out how much he makes per hour. and 48/3 = 16. So he makes $16 dollars an hour.