Answer:
D. 0.925x + 0.88y = 0.91(x + y)
Step-by-step explanation:
The important point to remember is that the total mass of pure silver is the same on each side of the equation.
0.925x = mass of pure silver in first alloy
0.88 y = mass of pure silver in second alloy
The final alloy has a mass of (x + y) g and is 91 % pure silver, so
0.925x + 0.88y = 0.91(x + y)
For every 3 girls, there are 4 boys. if there are nine girls, that expands to three extra boys, because for every three theres an extra one. so there are 12 boys (9+3.) the final ratio, boys to girls, is 12:9.
The answer is 17/80
Step by step:
Move decimal 2 to the left,
.2125
Then:
2125
____
10000
Then just simplify from there
Answer:
(a d)/(bc)
Step-by-step explanation:
a/b ÷ c/d
Copy dot flip
a/b * d/c
ad / bc
7.83 x 10^-7 (the *^* is where the power goes)
