-0.25 or -1/4 is the answer
Answer:
3026
30
Step-by-step explanation: Average sum of the female and male's test score is the sum of expected value of each gender:

Assuming x represents the random male selected and y represents the random female selected:

3026
The average sum of their scores is 3026.
Average difference is the difference between the expected value (mean) of each gender:

1528 - 1498
30
The average difference of their scores is 30.
Answer:
We can do it with envelopes with amounts $1,$2,$4,$8,$16,$32,$64,$128,$256 and $489
Step-by-step explanation:
- Observe that, in binary system, 1023=1111111111. That is, with 10 digits we can express up to number 1023.
This give us the idea to put in each envelope an amount of money equal to the positional value of each digit in the representation of 1023. That is, we will put the bills in envelopes with amounts of money equal to $1,$2,$4,$8,$16,$32,$64,$128,$256 and $512.
However, a little modification must be done, since we do not have $1023, only $1,000. To solve this, the last envelope should have $489 instead of 512.
Observe that:
- 1+2+4+8+16+32+64+128+256+489=1000
- Since each one of the first 9 envelopes represents a position in a binary system, we can represent every natural number from zero up to 511.
- If we want to give an amount "x" which is greater than $511, we can use our $489 envelope. Then we would just need to combine the other 9 to obtain x-489 dollars. Since
, by 2) we know that this would be possible.
Answer: Mode
<u>Step-by-step explanation:</u>
The given data set is: 10, 10, 12, 13, 15
Mean is the average - find the sum of the data set and divide by the number of terms in the set: 
Mean = 12
Median is the middle term (when the data set is ordered from least to greatest).
Median = 12
Mode is the term that appears the most.
Mode = 10
Since you want to show that the prices are low, you would choose the lowest value. 10 is lower than 12, so the Mode is lower than either the Mean or the Median.