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Answer:
- airplane: 225 mph
- wind: 45 mph
Step-by-step explanation:
The average speed with the wind is (540 mi)/(2 h) = 270 mi/h.
The average speed against the wind is (540 mi)/(3 h) = 180 mi/h.
Let a and w represent the speeds of the airplane and wind, respectively.
a + w = 270 . . . . speed with the wind
a - w = 180 . . . . speed against the wind
2a = 450 . . . . . . sum of the two equations
a = 225 . . . . . . divide by 2
w = a -180 = 45
The speed of the airplane is 225 miles per hour; the speed of the wind is 45 miles per hour.
Answer:
Step-by-step explanation:
Use the Quadratic formula:
You can identify that, in this case:
Now you need to substitute these values into the formula:
Remember that:
Therefore,rewriting and simplifying, you get:
Then, you get the following roots:
Exponential model because it's increasing rapidly.
-- The smallest perimeter you can make with a certain area
is a circle.
-- The NEXT smallest perimeter with the same area is a square.
With 1-ft by 1-ft square bricks, the shortest perimeter she could
make would be by using her bricks to make it as square as possible.
Without cutting bricks into pieces, the best she could do would be
(13 bricks) x (3 bricks) .
= (13-ft) x (3-ft)
Perimeter = (2 x length) + (2 x width)
= (2 x 13-ft) + (2 x 3-ft)
= (26-ft) + (6-ft) = 32 feet <== shortest perimeter.
-- Then, the more UNSQUARE you make it, the more perimeter
it takes to enclose the same area. That means Mary has to make
a rectangle as long and skinny as she can.
The longest perimeter she can make (without cutting bricks into
pieces) is (39 bricks) x (1 brick) .
= (39-ft) x (1-ft) .
Perimeter = (2 x length) + (2 x width)
= (2 x 39-ft) + (2 x 1-ft)
= (78-ft) + (2-ft) = 80 feet .
What she'll have then is a brick path, 39 feet long and 1 foot wide,
and when you walk on it, you'll need to try hard to avoid falling off
because it's only 1 foot wide.
Answer: B
Explanation:
32 marbles in total.
18 red marbles
4 blue marbles
10 green marbles.
You are asked what part of Osteen's marbles are red?
Probability = number of possible outcomes/total number of out outcomes.
P(Red) = 18/32 = 9/16
Both, 18 and 32 are divisible by 2 which gives 9/16. Since 9/16 cannot be reduced any further, we live it as it is. If you wanted to plug this into a calculator that would give 0.5625 which is 56.25% of Osteen's marbles are red.
P(Blue) = 4/32 = 1/8. 1/8 = 0.125 which 12.5% of his marbles are blue.
P(Green) = 10/32 = 5/16. 5/16= 0.3125 which 31.25 of his marbles are green. When you add 0.5625 + 0.125 + 0.3125 = 1 which is 100%. All probabilities add up to 1.
Hope this elaborate explanation helps.
