Answer:
Her speed on the summit was 35 mph.
Step-by-step explanation:
Her speed on the summit was "x" mph while her speed while climbing was "x - 10" mph. The distance she rode uphill was 55 miles and on the summit it was 28 miles. The total time she explored the mountain was 3 hours. Therefore:
time uphill = distance uphill / speed uphill = 55 / (x - 10)
time summit = distance summit / speed summit = 28 / x
total time = time uphill + time summit
3 = [55 / (x - 10)] + 28 / x
3 = [55*x + 28*(x - 10)]/[x*(x - 10)]
3*x*(x - 10) = 55*x + 28*x - 280
3x² - 30*x = 83*x - 280
3x² - 113*x + 280 = 0
x1 = {-(-113) + sqrt[(-113)² - 4*(3)*(280)]}/(2*3) = 35 mph
x2 = {-(-113) - sqrt[(-113)² - 4*(3)*(280)]}/(2*3) = 2.67 mph
Since her speed on the uphill couldn't be negative the speed on the summit can only be 35 mph.
Answer:
3 > -8
Step-by-step explanation:
-8 -7 -6 -5 -4 -3 -2 -1 <u>0</u> 1 2 3 ....
-8< 3
By normal curve symmetry
<span>from normal table </span>
<span>we have z = 1.15 , z = -1.15 </span>
<span>z = (x - mean) / sigma </span>
<span>1.15 = (x - 150) / 25 </span>
<span>x = 178.75 </span>
<span>z = (x - mean) / sigma </span>
<span>-1.15 = (x - 150) / 25 </span>
<span>x = 121.25 </span>
<span>interval is (121.25 , 178.75) </span>
<span>Pr((121.25-150)/25 < x < (178.75-150)/25) </span>
<span>is about 75%</span>
2,8 is the Awnser if you can see it on the graph it goes 2 up 8 right
Answer:
Area = 7.853981 in^2 (2.5 Pi)
Perimeter = 11.42478 in (3.63Pi)
Step-by-step explanation:
Area
Lg semi circle area = Pi(2^2)(0.5) = 3.141593(4)0.5) = 6.283185 in^2
Sm semi circle area = Pi(1^2)(0.5) = 3.141593(2)(0.5) = 1.570796 in^2
added together = 7.853981 in^2
Perimeter
Lg semi circle perimeter = Pi(4)(0.5) + 2 = 8.283185 in
Sm semi circle perimeter = Pi(2)(0.5) = 3.141593 in
added together = 11.42478 in
