Answer:
188 students would play sports, out of 1,000.
Step-by-step explanation:
If the probability that a random high school student plays a sport is 0.188 (150/800), which means for every 1 high school student 0.188 of them play a sport. Multiply 0.188x1,000 to get 188 students who play a sport.
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.
This is exactly like the one with the 'n's that you posted yesterday.
I guess you didn't get enough help on that one to understand it.
<span><u>7k/8 - 3/4 - 5k/16 = 3/8</u>
3/4 is the same as 6/8.
Add it to each side of the equation:
7k/8 - 5k/16 = 9/8
Multiply each side by 16 :
14k - 5k = 18
Add up the 'k's on the left side:
9k = 18
From this point, you can proceed directly to the numerical value of 'k'
if you need it.<u />
In your question, you said you need help, and I showed you how to
strip the problem down so that the only thing left is ' k = something '.
Giving you the answer is no help. Nobody actually needs the answer.
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