Answer:his speed in still air is 6 miles per minute.
the speed of the wind is 1 mile per minute.
Step-by-step explanation:
Let x represent his speed in still air.
Let y represent the speed of the wind.
It takes Jack Frost 5 minutes to fly 35 miles with the wind. This means that his total speed would be x + y
Distance = speed × time
It means that
35 = 5(x + y)
35 = 5x + 5y - - - - - - - - - - -1
It takes him 7 minutes to go 35 miles against the wind. This means that his total speed would be x - y
It means that
35 = 7(x - y)
35 = 7x - 7y - - - - - - - - - - -2
Multiplying equation 1 by 7 and equation 2 by 5, it becomes
245 = 35x + 35y
175 = 35x - 35y
Adding both equations, it becomes
420 = 70x
x = 420/70 = 6
Substituting x = 6 into equation 1, it becomes
35 = 5 × 6 + 5y
35 = 30 + 5y
5y = 35 - 30 = 5
y = 5/5 = 1
Answer:
The length of the pother piece of the wood is 25 cm.
Step-by-step explanation:
Let the length of a piece of wood is x such that the ratio of two pieces is 2:5. Two pieces are 2x and 5 x
Length of the first piece is 10 cm. It means, 2x = 10 i.e. x = 5
We have considered that the length of other piece is 5x. It means 5×5 = 25 cm.
Hence, the length of the pother piece of the wood is 25 cm
Answer:
5°F
Step-by-step explanation:
Given that the average is obtained from;
Average = sum of scores / number of scores
Average temperature = 19.8°F
Let the temperature of the fifth day be x
Hence;
19.8 = 32 + 30 + 22 + 10 + x/5
19.8 = 94 + x/5
x= (5×19.8) -94
x= 5°F
Answer:
B. 150 yards
Step-by-step explanation:
Area of a Triangle = .5 * Base * height
So we need the height of the triangle, or the missing side.
We have to use Pythagorean Theorem to solve this:
A^2 + B^2 = C^2
15 ^ 2 + B ^ 2 = 25 ^2
b^2 = 25^2 - 15 ^ 2
b^2 = 625 - 225
b^2 = 400
sqrt (400) = 20
The missing height is 20. Now we plug it into 1/2 * b * H
.5 * 15 * 20
7.5 * 20 = 150
150 Yds