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
 
        
             
        
        
        
Answer:
15 km
Step-by-step explanation:
9:30 to 12:00 = 2.5 hours
2.5 x 6 = 15
 
        
                    
             
        
        
        
Answer:
ithink its A miight be wrong tho hope it helps in someway ig idk
Step-by-step explanation:
 
        
                    
             
        
        
        
Yes this question is correct
        
             
        
        
        
Answer:Its been 5 hours. so 85 - 82 = X. X times 0.6 = 5 then translate to 5 hours.
Step-by-step explanation: