Math Help

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Question: Please Help With Math permutations problem?

1. In how many different ways can 6 knights be seated in 6 chairs around a round table?

2. In how many different ways can 9 people be lined up in a row if 2 of them must stand next to each other?

3. The manager of a baseball team wants the best hitter up fifth. If the lineup consists of 9 players, how many different lineups are possible?

Answer: 1. Since you specified a round table, I will assume it does not matter if you shift everyone around keeping them in the same order. Put 1 person in any seat. Then you can choose among 5 people to sit to his right, 4 people to sit to the right of that person, etc. So you have 5*4*3*2*1 or 120 ways.

2. Count the 2 people who must stand next to each other as 1 person. so you have 8*7*6*5*4*3*2 = 40320 ways. Or you can switch the order of those 2 people, giving you another 40320 ways, for a total of 80640.

3. The best hitter is fifth, so you can rearrange the other 8 players in 8*7*6*5*4*3*2*1 = 40320 ways.

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Question: How can i solve these 2 math word problems?

1. it takes Nana 12 days to type her thesis. a professional typist could type it in 8 days. How long would it take to type the thesis if both worked together?

2. One car travels 30 m.p.h faster than another. In the same time that one travels 200 miles the other goes 320 miles. Find the rate of each car.

in problem 2 i know that i have to use the formula D=RxT but i do not what goes where in the formula

Answer: 1) if Nana needs 12 days, that would mean that she finishes 1/12 of the paper in 1 day, similarly it would mean that the pro finishes 1/8. use this formula: 1= x (1/12 + 1/8) and solve for x.

the formula means, to finish the whole paper, it would take x days for nana (1/12) and the pro (1/8) working together.

you will get 4.8 days.

2) set the speed one one car x, the speed of the other car would be x+30.

use the formula D = RxT, you will get 1 equation for each car.

car 1: 200 = x *T

car 2: 320 = (x+30) *T

T is the same for both cars, so solve for T for each equation and set the T’s equal to each other.

you will get the equation 200/x = 320/(x+30), cross multiply you would get 200(x+30) = 320 x

solve for x, you will get x= 50

so car 1 = 50 mph, car 2 = 80 mph

Math Word Problems Sample Clip

Question: Quick Math Help? ?

How do you graph Absolute Value functions off of a graph? Like, let’s use the coordinates (2, -5) just as an example. I also need to know how to do the same with a quadratic function (let’s use the same coordinates) and with a cubic function (same coordinates).

Thank you so so much. I have a math project due Friday (we have to draw a design on a graph, make the points, then write them or something like that. I’m failing math for a reason) and I have to follow these wierd specific guidelines. Any kind of help you can give me will be most appreciated!

I would also love it if you list some sources (like math websites that explain this kinda stuff. Couldn’t find anything on math.com or purlemath.com.) just so I can have some references if I need more help.

Love much!
Beth.

Answer: Just make y positive and you’re done.

No sources because you can use common sense. If there’s a absolute values around f(x) = |whatever|, if the whatever is supposed to negative in the normal graph, then in the Absolute Value graph it’s the same distance from the x-axis except positive.

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