Answer: 8 7/10 hours
whole part = 8
fractional part = 7/10
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Work Shown:
x = number of hours driving
(5/6)x = total number of gallons of gas used
(5/6)x = 7 & 1/4
(5/6)x = 7 + 1/4
(5/6)x = 28/4 + 1/4
(5/6)x = 29/4
x = (29/4)*(6/5)
x = (29*6)/(4*5)
x = 174/20
x = 87/10
x = (80+7)/10
x = 80/10 + 7/10
x = 8 + 7/10
x = 8 & 7/10
This is the same as writing 8 7/10
Amy drove 8 full hours, plus an additional 7/10 of an hour.
That mixed number converts to the decimal value 8.7
First you want to combine like terms. on the first equation we can combine 2x+x=3x. So now we have 3x-3. On the right side we can combine 12+1 so we now have -x+13. Now we will take add an x to -x so it's 0 but we have to do it to the other side as well so now we have 4x-3=13. now we will add three to -3 to make it 0 but again we have to do it to the other side. Now we have 4x=16. We want to figure out what x is so we now divide 4x by 4 so we are just left with x but we need to do it to the other side so your answer is x=4
1. First, put the range in order and then divide the set into quarters. In this case, quartiles are between numbers.
<span>83, 85, 89, l 91, 95, 104, l 112, 118, 118, l 125, 134, 138
Q</span>₁ = (89 + 91)/2 = 90
Q₂ = (104 + 112)/2 =108
Q₃ = (118 + 125)/2 = 121.5
Interquartile range (IQR) = Q₃ - Q₁
= 121.5 - 90
IQR = 31.5
2. To find the standard deviation follow the simple steps.
Formula in finding the standard deviation: (see attached file)
Step 1. Work out the simple average of the numbers (mean)
<span><span><u>212 + 249 + 212 + 248 + 239 + 212 + 216 + 234 + 248</u>
</span> 9
= <span><u>2070</u>
</span> 9
mean (</span>μ) = 230
Step 2. Subtract the mean on each number and square the result.
212 - 230 = (-18)² = 324<span>
249 </span>- 230 = ( 19)² = 361<span>
212 </span>- 230 = (-18)² = 324<span>
248 </span>- 230 = (18)² = 324<span>
239 </span>- 230 = (9)² = 81<span>
212 </span>- 230 = (-18)² =324<span>
216 </span>- 230 = (-14)² =196<span>
234 </span>- 230 = (4)² =16<span>
248 </span>- 230 = (18)² =324
Step 3. Add all the squared results and get the mean.
<span><u>2274</u>
</span> 9
Variance = 252.6666667
Step 4. Get the square root of the variance.
√252.6666667
= 15.89549202