We can set up an equation to solve this problem, but first we need to write out what we know.
$20 overall
$0.24 every minute
$13.52 remaining on the card
Now that we know our information, we can set it up in an equation.
20 - 0.24x = 13.52
The 20 represents $20 overall when she first got the phone card.
We are then subtracting $20 from how must it costs a minute (which is 24 cents). The 'x' indicates the number we are trying to find (how many minutes her call lasted). Lastly, 13.52 is the result of everything, since she has $13.52 remaining on the card.
We can now solve the equation:
20 - 0.24x = 13.52
-0.24x = 13.52 - 20 /// subtract 20 from each side
-0.24x = -6.48 /// simplify
x = 27 /// divide each side by -0.24
Our solution is: x = 27.
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An easier way to solve this problem would be to first, subtract the total amount of money she had on the card when she first got it, and then the remaining total she ended up with.
$20 - $13.52 = $6.48
So, she spent a total of $6.48 on long distance calls, but since we are looking for how many minutes, we need to divide the total she spent and how much it costs per minute.
6.48 ÷ 24 = 27
We receive the same amount of minutes spent just like we did the last way we solved.
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Salma spent 27 minutes on the phone.
Answer:
Option D
Step-by-step explanation:
A reporter collects a random sample of 50 runners from all the runners who finished the Cherry Blossom Ten Mile Run in 2009 and constructs a 99% confidence interval for the true mean finish time to be (86.05, 99.38) minutes.
Assuming the reporter performed the calculations correctly, which of the following statements are appropriate interpretations of this confidence interval?
We can expect that 99% of confidence intervals created using the same method the reporter used will contain the true mean run time for runners of this race.
Answer:
cosS is 33/65
Step-by-step explanation:
Linear fonction's equation : y = ax
So only in y = 2x
2 is the constant of <span>proportionality</span>
