MuffinMan17

4 socks at x dollars each means that the total for the socks was 4x. 3 shirts at 3x dollars each means that the total cost for the shirts was 3(3x) which equals 9x. Add 9x and 4x together for the total cost of the shirts and the socks to get 13x, and since the total cost which is 13x equals 19.50, you can solve for x. x = 1.5, and since the cost of one shirt is 3x, that equals 3(1.5) which equals 4.50

AmirElbanna

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I need tthe answer of. This question plz and there are some other ones

AmirElbanna

The other one here



http://img211.imageshack.us/img211/4...2110100226.jpg

SalmaThabet

if a taxicab driver charges $0.60 for the first 1/3 mile and $0.40 for each 2/5 mile, or part there of ,after that, aride costing $ 3.80 could be at most how many miles long ? the answer is 53/15

HarveyMuddLove

@Amirr

I believe for question 1 the answer would be 72 choices
- first seat one of the people, they can sit in any seat, so 12 choices. Next person can't be in same row or column, so they can only sit in the 6 remaining seats (i.e. 2 rows and 3 seats each row not in same column), so 6 x 12 = 72..

Answer for the 2nd question is: 54
- Since f(n+3) = 3f(n), f(7+3) = f(10) = 3f(7), then f(7) = f(4+3) = 3f(4), and from the table, f(4) = 6, so f(7) = 6x3 = 18. Then 3f(7) = 3x18 = 54 = f(10)

And ^ 3.80 - 0.60 = 3.20 dollars to spend on rest of trip. Since each 2/5 mile is 0.40, divide 3.20 by 0.40 to find out x 2/5 miles, comes out at 8 of those 2/5 miles. 8 x 2/5 + first 1/3 mile is 53/15

KennyP

The average (arithmetic mean) of the test scores of a class of p students is 70, and the average of the test scores of a class of n students is 92. When the scores of both classes are combined, the average score is 86. What is the value of p/n (p divided by n)?

I did 70p + 92n/ p+n = 86. My final equation was 16p =6n. My answer was 16p over 6n. The real answer is 3/8 or essentially 6/16. Can someone explain this? Since its asking for p/n dont you divided 16p/6n?? Im confused

AmirElbanna

I need this question PLZ


Math help center


the second one is

A perfectly spherical scoop of ice cream is to be divided by three cuts. What is the greatest number of pieces that can result from this division?

a)3
b)4
c)6
d)7
e)8

the answer is e

AmirElbanna

qaq7y.jpg at Free Image Hosting

RandomHSer

@amir
imagine that the ice cream scoop is centered at the origin. It is broken into 8 parts by the octants formed by the three axis.

scourge566

1. In the xy - coordinate plane, the graph of x = y^2 - 4 ( x equals to y square minus 4) intersects line L at (0,p) and (5,t). What is the greatest possible value of the slope L?

2. Esther drove to work in the morning at an average speed of 45 miles per hour. She returned home in the evening along the same route and averaged 30 miles per hour. If Esther spent a total of one hour commuting to and from work, how many miles did Esther drive to work in the morning?

These questions from old( 8 practice set) BB practice set 1 section 6. Guys if you have the old BB then could u also help me with #5>page 408 and #13>page 411...I repeat, it's from the old BB (8 practice sets). Any help would be appreciated. :-)

scourge566

Btw guys, I'm mainly having problem with the "probability" and "graph" questions..what do you recommend for improving these two math portions??

Reckie

2. Let's say that the time it took her to get to work in the morning is t hours. Then the time it took her to get home in the afternoon must be 1-t hours. We know that for any trip, distance equals rate times time or d=rt. That means that the distance she drove to work is given by d=45t, but we also know that the distance she drove to get home must be the same distance, because she took the same route (and, presumably, no one picked up her house and moved it while she was at work) so for the trip home we can say and since the distances are equal, we can say: d=30x(1-t)

45t=30x(1-t)
45t=30-30t
75t=30

t=30/75=2/5 @45mph

d=45 X (2/5)=18 miles

scourge566

@ Reckie Wow! Thanks for the answer!!

What about question 1? Didn't you try it?

DrSteve

For the second one you can also use the harmonic mean formula (aka Xiggi's formula here):

avg rate for round trip = 2(rate 1)(rate 2)/(rate 1 + rate 2) = 2(45)(30)/(45+30) = 36.

So 2d = (36)(1) = 36, and d = 18.

DrSteve

For the first one, plug the two points into the given equation (they are on the graph after all):

You get 0 = p^2 - 4. So p=2 or p=-2
You also get 5 = t^2 - 4. So t^2 = 9. Thus, t=3 or t=-3.

Now the slope of the line is (t-p)/5. You can reason out which values for t and p will give the greatest slope, or to be safe you can just try all 4 possibilities:

(3-2)/5=1/5, (3--2)/5=5/5=1, (-3-2)/5=-5/5=-1, (-3--2)/5=-1/5.

So the gretaest value is 1.