Answer:
1) James brother is 10-x years old
2) James was 3 years ago x-3 years old
3) James brother was 3 years ago 7-x years old
4) 3(x-3)=7-x
5) James is 4 years old, his brother is 6 years old
Step-by-step explanation:
3) 10 - x - 3 = 7 - x
5) 3* James age 3 years ago = James brothers age 3 years ago
<=> 3*(x-3) = 7-x
<=> 3x - 9 = 7 - x
<=> 4x = 16
<=> x = 4
x = quarts of 30% acid solution
y = quarts of 65% solution
x + y = 175
Each quart of the 30% solution contributes 0.30x quarts of acid; similarly, each quart of the 65% solution contributes 0.65y quarts of acid. So
0.3x + 0.65y = 0.55*175 = 96.25
That is, the chemist wants 175 quarts of a new mixture with a 55% concentration of acid, which comes out to 95.25 total quarts of acid. The total amounts of acid from either sides of this equation must balance out.
Now solve for x and y:
x + y = 175 ==> y = 175 - x
0.3x + 0.65y = 96.25 ==> 0.3x + 0.65(175 - x) = 96.25
==> 0.3x + 113.75 - 0.65x = 96.25
==> 17.5 = 0.35x
==> x = 50 ==> y = 125
So we need to find a number that has the same ratio to 64 as 3 has to four. We do this by diving 64 into 4:(this is 16): so the two ratios are different by 16. To find the remaining number we multiply 3 by 16: this is 48. So 48 has the same ratio to 64 as 3 has to 4.
And 48 is the answer!
Answer:
6×1 7×
Step-by-step explanation:
that's the answer
Answer:
8762
Step-by-step explanation:
