Answer: $40
Step-by-step explanation:
The key formula to use for this problem is the simple interest formula, which is 
; where I is the interest earned, p is the principal (initial) amount, r is the interest rate, and t is the amount of time that passes.
Since we know that both investments have the same interest rate, we can use the information from the first part of the problem to solve for the interest rate. Using algebra, we can rearrange the simple interest formula to solve for the interest rate: 
. We know that our interest earned is $24 and our principal amount is $300. To make things easier, we'll also convert months to years, which is easy to do since we know that 12 months = 1 year. This gives us our value for the amount of time that passes. Now, all we have to do is plug in our values into the rearranged equation above.
We should now have: 
Now, to find the interest earned from the $500 investment, we just need to plug in our values from the second part of the problem, along with our calculated interest rate of 0.08, into the original formula of
This should result in 
Therefore, James will receive $40 on his $500 investment after 12 months.
Answer:
Step-by-step explanation:
The table shows a set of x and y values, thus showing a set of points we can use to find the equation.
1) First, find the slope by using two points and substituting their x and y values into the slope formula, 
. I chose (-3, 13) and (0,17), but any two points from the table will work. Use them for the formula like so:
Thus, the slope is 
.
2) Next, identify the y-intercept. The y-intercept is where the line hits the y-axis. All points on the y-axis have a x value of 0. Thus, (0,17) must be the y-intercept of the line.
3) Finally, write an equation in slope-intercept form, or 
format. Substitute the 
and 
for real values.
The represents the slope of the equation, so substitute it for . The represents the y-value of the y-intercept, so substitute it for 17. This will give the following answer and equation:
Answer:
The temperature at 9 am = -14.7°F
Between 9am and 12 pm = -14.7 + 17.8 = 3.1°F
Between 12pm and 3 pm = 3.1+5.1 = 8.2°
Between 3pm and 6 pm = 8.2-14.5 = -6.3°F
Answer:11
Step-by-step explanation:
Boys : girls=7:1
Sum of ratio=7+1=8
Let them number of girls be y
Then they number of boys=y+66
Total number of pupils=y+y+66
Total number of pupils=2y+66
Number of girls=(girls ratio)/(sum of ratio) x (total number of pupils)
y=1/8 x (2y+66)
Cross multiply
y x 8=2y + 66
8y=2y + 66
Collect like terms
8y-2y=66
6y=66
Divide both sides by 6
6y/6=66/6
y=11
The number of girls is 11
The area of a triangle is base length x height then divide all by 2,
so 12 x 10 /2
=60 ft²
