math - help immediately ?
I substitute for high school math, and I was given this package by the teacher, but I don't understand these three questions. Can somebody help me explain. I know how to do it, but cannot explain it.
Point P is on Line Segment AB. AB = 20 and AP / PB = 5 / 3. How long is AP?
The ratio of 2k - 7a to 3k + a = 3 / 2, then the ratio of k to a is ......?
A study showed that 68% of men and 59% of women voted in favour of Mr.Potus. If everyone voted (all the men and women), and 66% of the people voted yes. What is the ratio of men to women?
- 1 decade agoBest Answer
Therefore, 3AP=5PB, AP=5PB/3
Substitute in AP+PB=20
Mulitply by 3 throughout, 5PB+3PB=60
(ii) second question
Multiply by (3k+a) throghout
Answer: The ratio of k/a is -11/5
(c) Let there by x men and y women
the total people voted = total men + total women = x+y
66% voted yes i.e 0.66(x+y) voted yes
68% of men voted = 0.68x
59% of women voted = 0.59y
the total people voted in favor of Mr. Potus =0.68x+0.59y
But this is also equal to 0.66(x+y)
Answer: The ratio of men to women is 3.5.
- r9ohcopLv 51 decade ago
1. line segment of total length 20. Place a point somewhere in the line segment, so that the ratio of the two new line segments is 5/3. Solve for the length of the two new line segments.
5/3 = 5x / 3x = 5x:3x
5x + 3x = 20, x = 20/8.
so the two lengths are 5(20/8) and 3(20/8)
2. you have (2k - 7a) / (3k + a) = 3/2 and you want to know k/a
cross multiply (think that's what it's called).
(2k - 7a)(2) = (3k + a)(3)
4k - 14a = 9k + 3a
move the k's to one side and the a's to the other.
-17a = 5k
k = (-17/5)a or the ratio of k/a = -17/5
3. let the number of men = x and the number of women = y
there are a total of x+y people, and the amount of people is equal to the amount of votes.
Mr. Potus won 66% of the total vote, or .66(x + y)
.68x + .59y = .66(x + y)
distribute and then move the x's and y's to different sides.
.68x + .59y = .66x + .66y
.02x = .07y
x = .07y/.02 or 7/2y
so the ratio is 7 men to 2 women.
- 1 decade ago
for the first one: so if the line is 20 units long and ap is 5/(5+3) so 5/8 the length of ab then 5/8 * 20 = 12.5 units.