The average speed is the distance divided by the time.
Total distance:
12.8 miles + 17.2 miles = 30 miles
Total time:
noon - 9:00 a.m. = 3 hours
6:00 p.m. - 1:00 p.m. = 5 hours
Total time = 3 hours + 5 hours = 8 hours
average speed = 30 miles / 8 hours = 3.75 miles per hour
Answer:
10 1/8 years?
I hope this is right!
Step-by-step explanation:
Answer:
See below.
Step-by-step explanation:
a.
The first figure has 1 square. The second figure has a column of 2 squares added to the left. The third figure has a column of 3 squares added to the left. Each new figure has a column of squares added to the left containing the same number of squares as the number of the figure.
b.
Figure 10 has 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55 squares.
c.
The formula for adding n positive integers starting at 1 is:
1 + 2 + 3 + ... + n = n(n + 1)/2
For figure 55, n = 55.
n(n + 1)/2 = 55(56)/2 = 1540
d.
Let's use the formula set equal to 190 and solve for n. If n is an integer, then we can.
n(n + 1)/2 = 190
n(n + 1) = 380
We know that 380 = 19 * 20, so n = 19.
Answer: yes
e.
Use the formula above,
S = n(n + 1)/2, where S is the sum.
f.
n(n + 1) = 1478
38 * 39 = 1482
37 * 38 = 1406
6x-1=4x+6
subtracting 4x from each side
2x-1=6
adding 1 to each side
2x=7
divide by 2
x=7/2 or 3.5
check: 6(7/2) -1 =4(7/2)+6
21-1 =14+6
20=20 correct
Answer:
9
Step-by-step explanation:
