Answer:
s - 20 = 60 km/hr
Step-by-step explanation:
The distances are the same going there and coming back.
So
Givens
d = 400
2/5 * d = 2/5 * 400 = 160
The rest of the trip back = 400 - 160 = 240
Equation
400/(s) + 160/s + 240/(s - 20) = 11 hours.
Solution
distance / speed = time or
d/s = time
Multiply through by s*(s - 20)
400*(s - 20) + 160*(s - 20) + 240s = 11*s*(s - 20) Remove the brackets.
400s - 8000 + 160s - 3200 + 240s= 11(s^2 - 20s) Collect like terms on the left.
560s - 11200 + 240s = 11(s^2 - 20s) Remove the brackets on the rt.
800s - 11200 = 11s^2 - 220s Switch and add 220s
11s^2 - 220s + 220s = 800s +220s - 11200 Combine
11s^2 = 1020s - 11200 Put everything on the left.
11s^2 - 1020s + 11200 = 0
this quadratic factors into
(11s - 140 )(s - 80) = 0
You have 2 solutions
11s - 140 = 0
11s = 140
s = 140/11
s = 12.727272... This solution won't work because the speed has no room to drop down 20 km / hour
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s - 80 = 0
s = 80 km hour
But that is not the answer
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The answer you want is s - 20 which is 60 km/hr.
In triangle STU, the possible values for ∠S, derived by using the law of sines, are approximately 10.2° and 169.8°.
The student wants to find all possible values of ∠S in ΔSTU, s=1.6 cm, u = 9.5 cm and ∠U=24°. This is a problem involving the laws of sines and cosines in trigonometry. By using the law of sines, we can find ∠S = sin⁻¹ ((sin U * s) / u) ≈ 10.2° or 169.8° (since sinx is positive in both the 1st and 2nd quadrants). It is important to note that ∠S and ∠U are not complimentary angles in a right triangle, therefore, both possible values of ∠S are valid if they meet the condition that the sum of ∠S, ∠T and ∠U should be equal to 180° in ΔSTU.
#SPJ1
The distance of salmon from the surface of the water is 8 feet.
Calculate the answer using a math operator is referred to as a mathematical operation.
Basic mathematical operations are addition, multiplication, subtraction and division.
Given that,
The distance of school of salmon for the surface of the river = 5 feet.
Since, to escape a hungry bear, the school of salmon went down to 3 feet.
The position of the salmon to the surface = 5 + 3 = 8 feet.
The required distance of school of salmon from the surface of water is 8 feet.
To learn more about Mathematical operations on :
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Answer:
8 Feet below the surface
Step-by-step explanation:
If the salmon were initially 5 feet below the surface, and then travelled down an additional 3 feet from the initial 5, then the new position would be 8 feet down relative to the surface.
You can write this as -5 + -3 = -8, assuming that 0 represents surface level.
Cheers.
a. the distribution will exhibit symmetry.
b. the distribution will exhibit a positive skew.
c. the distribution will exhibit a negative skew.
d. the distribution will uniform throughout.