math questions?

Question

1. a set of data contains 10 negative numbers and 4 positive numbers. Which one of these statements must be true?
a. the mean is a negative number
b. the median is a negative number
c. the mode is a negative number
d. the range is a negative number



2. Which expression represents 270,000 written in scientific notation?
a. 270 x 10^3
b. 27 x 10^4
c. 2.7 x 10^5
d. 0.27 x 10^6

Answer 1

1. b
2. c

Answer 2

the first one isn't necessarily a or b or c because we don't know the values of the negative or positive numbers, but we do know the quantity of pos and neg, therefore the answer is c - the mode is neg. because there are more neg. numbers than pos.

and the second one is also c because there are 5 placements of ten from between the 2 and the 7 to the decimal place, and you generally want the number to have the decimal between the first two numbers for scientific notation.

Addendum - most people are saying b is the correct answer for 1, and that may be true, but without knowing the values, one cannot tell if b or c is the correct one.
The mode is the number that occurs the most and it is true we don't know if any of the numbers are repeating, either pos. or neg.
But the median is the number right in the middle of all of the values, and again we see it is true that we need to know if any of the numbers are repeating.
So either b or c CAN be correct, but essentially an arguement can be made that there simply isn't enough information to discern which one is true.

Ex: say you have (-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, 2, 1, 3, 2 )as your data set (10 neg numbers and 4 pos)
IN this case the mode is neg but the median is pos.

Conversly, suppose you have (-10,-9,-8,-7,-6,-5,-4,-3,-2,-1, 1,2,2,4) as your data set,
Here you have a pos mode (2), and a neg median.

Answer 3

1 = b, 2 = c

Answer 4

I think is


1.- b ( if the negative ones are bigger than positive ones)

Median= {(X(n/2)+X((n+2)+1)}/2 if n=is odd
=X((n+1)/2 n=is even

But it can be also c because we have more negative numbers than positive ones, remember the mode is the number that repeat more times.


2.- All are right. The exponent is the number of places that you have to move the point but i have to choose I prefer letter C

Answer 5

I see your mix up - A = PiR^2 authentic? nicely, area = Pi (radius squared), the position you position the radius as 40 8. The Diameter is 24 cm, authentic? nicely, contained in the formula, radius is merely 1/2 of the diameter, so so that you could be using 12^2, no longer 40 8^2 Your formula could look as if this: area = Pi(3.14) * 12^2 That'll provide you the right answer.

Answer 6

#1. only b has to be true for any data set.

#2. c is the only number written in scientific notation.

Hope this helps. Good Luck.

Answer 7

If you knew the meanings of all of these terms, you would be able to answer these questions.

You should review the explanations for mean, median, mode, range, and scientific notation.

Answer 8

1.b 2.c........is this a tick question? ;p

Answer 9

b
c