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need help on these questions


queborg

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1

 

In the xy-plane, line n passes through the origin and has slope 4. If points (1, c) and (d, 2) are on line n, what is the value of c/d ?

 

A.0.25

 

B.0.5

 

C.2

 

D.4

 

E.8

 

 

2

The charge for a single room at Hotel P is 25 percent less than the charge for a single room at Hotel R and 10 percent less than the charge for a single room at Hotel G. The charge for a single room at Hotel R is what percent greater than the charge for a single room at Hotel G ?

 

A. 15%

B. 20%

C. 40%

D. 50%

E.150%

 

3

If d = 1 / 2^3 * 5^7 is expressed as a terminating decimal, how many nonzero digits will d have?

 

A.One

B.Two

C.Three

D.Seven

E.Ten

 

4 If M is the least common multiple of 90, 196, and 300, which of the following is NOT a factor of M ?

 

A. 600

B. 700

C. 900

D.2,100

E.4,900

thanks a ton

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  • 3 weeks later...

1)

y = mx + s (where m is the slope and s is constant)

 

 

y = 4x + s

 

0 = 4(0) + s (since this passes through origin)

=> s=0

y=4x is the equation

 

substituting values of 2 coordinates in this eq.

c=4(1) ----eq1

2=4(d)

=> d = 1/2 ----eq2

 

dividing eq1 and eq2

c/d=8

 

 

2)

 

Let rate in R = x

=> rate in P = .75x ----1

 

Let rate in G = y

=> rate in P = .9y ------2

 

equating 1 n 2

.75x=.9y

or x = 1.2 y

so rate in Hotel R is 20% more than G

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3)

 

I am not sure if this d = 1 / 2^3 * 5^7 means d = 1 /( 2^3 * 5^7) or this means d = 5^7/ 2^3?

 

If its the first one.

 

1/(2^3 * 5^3 * 5^4)

 

1/(10^3*5^4)

 

multiplying num and den by 10^4

10^4/(10^7*5^4)

 

(10/5)^4/(10^7)

 

or 2^4/10^7

so it has 7 decimal digits

 

 

4) Finding LCM of 90, 196 and 300

 

=> 9 * 25 * 49 * 4

=> 9 * 49 * 100

 

so 600 is not a factor

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  • 2 weeks later...
3)

 

I am not sure if this d = 1 / 2^3 * 5^7 means d = 1 /( 2^3 * 5^7) or this means d = 5^7/ 2^3?

 

If its the first one.

 

1/(2^3 * 5^3 * 5^4)

 

1/(10^3*5^4)

 

multiplying num and den by 10^4

10^4/(10^7*5^4)

 

(10/5)^4/(10^7)

 

or 2^4/10^7

so it has 7 decimal digits

 

 

The question asks for non-zero digits, so how can we conclude that there are 7 decimal digits since these 7 digits are inclusive of zero? Isn't the answer 1?? What is the OA?

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  • 2 weeks later...
How did you determine that 600 is not a factor ?:hmm:

 

LCM : 9 x 100 x 49

 

can be rephrased as 9 x 100 x 7 x 7 -> 700 is a valid factor

 

can be rephrased as 9 x 100 x 49 -> 900 is a valid factor

 

can be rephrased as 3 x 3 x 100 x 7 x 7 -> 2100 is a valid factor

 

can be rephrased as 9 x 100 x 49 -> 4900 is a valid factor

 

can't be rephrased similarly for 600 , hence 600 is the answer

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I agree. I think by non-zero digits, it is referring to the decimal part so it should be seven.

 

3.

 

16*10^-7 means 0,0000016 and "any decimal that has only a finite number of nonzero digits is a terminating decimal. for example, 24, 0.82, and 5.096 are three terminating numbers."

 

according to this info the answer is 7

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