Answer:
the answer your looking for is a pyramid
Step-by-step explanation:
Answer: 912
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Work Shown:
The starting term is a1 = 3. The common difference is d = 5 (since we add 5 to each term to get the next term). The nth term formula is
an = a1+d(n-1)
an = 3+5(n-1)
an = 3+5n-5
an = 5n-2
Plug n = 19 into the formula to find the 19th term
an = 5n-2
a19 = 5*19-2
a19 = 95-2
a19 = 93
Add the first and nineteenth terms (a1 = 3 and a19 = 93) to get a1+a19 = 3+93 = 96
Multiply this by n/2 = 19/2 = 9.5 to get the final answer
96*9.5 = 912
I used the formula
Sn = (n/2)*(a1 + an)
where you add the first term (a1) to the nth term (an), then multiply by n/2
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As a check, here are the 19 terms listed out and added up. We get 912 like expected.
3+8+13+18 +23+28+33+38 +43+48+53+58 +63+68+73+78 +83+88+93 = 912
There are 19 values being added up in that equation above. I used spaces to help group the values (groups of four; except the last group which is 3 values) so it's a bit more readable.
Hey there mate!
Please check the attached answer of picture for explanation.
1 hour = 60 minutes.
Convert the minutes to decimals by diving by 60
30/60 = 0.5
2 hours and 30 minutes = 2.5 hours
45/60 = 0.75
5 hours 45 minutes = 5.75 hours
15/50 = 0.25
3 hours 15 minutes = 3.25 hours
Ow add all the hours:
2.5 + 5 + 5.75 + 3.25 = 16.5 hours
Answer: B. 16.50
