Solution :
It is given that a psychologist wants to determine the difficulty of the task influences on the estimate of how long people spend working on it.
Now we have to describe a experiment by using a completely randomized design and learn the effect of the difficulty on the estimated time is by randomly assigning 15 students to a Group 1 of easy mazes and other 15 students to the second group 2 of hard mazes. And then we compare the time estimates of the two groups.
Answer:
C
Step-by-step explanation:
Using rule of negatives and positives:
The rules for multiplication and division are simple: If both numbers are positive, the result is positive. If both numbers are negative, the result is positive. If one number is positive and the other is negative, the result is negative.
This is why C is the correct statement
Answer:
Step-by-step explanation: <u>Speed</u> is distance an object travelled per unit time.
It is represented by letter v and can assume various units.
1) 
v = 18 miles per hour
Her average speed is 18 mph.
2) Rearraging formula for distance:
d = v.t
d = 70 * 4
d = 280 miles
You would travel 280 miles.
3) 
v = 52.5 mph
My average speed is 52.5 mph.
4) Rearranging formula to determine time:
t = 2.34 hours
It will take 2 hours and half to arrive in Leeds. So, we will be expected to arrive at 12:04.
5) The unit change but the way of calculating time is the same.
t = 500 s
or t = 8.34 minutes
It will take, for an athlete to run 2000m, 8.34 minutes.
6) a) All units must match, so for a speed in mph:
45 minutes is 0.75 hours. Total time is 8.75 hours.
v = 560 mph
The average speed is 560 mph.
b)
t = 6.67 hours
Sam will take 6.67 hours to covered the distance.
If Heather puts in 1.36% of her salary into a retirement account and she makes $63,000 in a year, this can be solved by 1.36% x 63000. First convert 1.36% into a decimal. To do this, divide by 100.
1.36/100=0.0136
1.36% x 63000
=0.0136 x 63000
=856.8
Heather would put $856.8 in for the whole year. To find how much per month, divide by 12.
856.8/12=71.<span>4
</span>Rounded to the nearest dollar is $71.
Heather would put $71 into a retirement account each month.
<em>
</em><em>Note: This was solved by multiply the percent and then dividing by 12 months. You could also do this by dividing by 12 months first and then multiplying the percent.</em>
Step-by-step explanation:
You can find the area of a right triangle the same as you would any other triangle by using the following formula:
A = (1/2)bh, where A is the area of the triangle, b is the length of the base and h is the height of the triangle; However, with a right triangle, it's much more convenient in finding its area if we utilize the lengths of the two legs (the two sides that are shorter than the longest side, the hypotenuse and that are perpendicular to each other and thus form the right angle of the right triangle), that is, since the two legs of a right triangle are perpendicular to each other, when we treat one leg as the base, then, consequently, we can automatically treat the length of the other leg as the height, and if we initially know the lengths of both legs, then we can then just plug this information directly into the area formula for a triangle to find the area A of the right triangle.
For example: Find the area of a right triangle whose legs have lengths of 3 in. and 4 in.
Make the 4 in. leg the base. Since the two legs of a right triangle are perpendicular to each other, then the length of the other leg is automatically the height of the triangle; therefore, plugging this information into the formula for the area of a triangle, we have:
A = (1/2)bh
= (1/2)(4 in.)(3 in.)
= (1/2)(12 in.²)
A = 6 in.² (note: in.² means square inches)
