Answer:
r=2
Step-by-step explanation:
y = k x^r is the formula for a direct variation
y = k x^ -r is the formula for a indirect variation
20= 5 (1/2)^ -r
Divide each side by 5
4 = (1/2) ^ -r
Rewriting
2^2 = 2^ -1 ^ -r
2^2 = 2 ^ r
The bases are the same so
2 =r
Answer:
Hello there, I love answering these questions!
Step-by-step explanation: turn 3/4 into 6/8 = 3x2/4x2 then subtract. 6/8 - 3/8 = 3/8
Hope this helped you! Have a wonderful day!
The hundred thousands place is the 2. Since the place below that is 0, it rounds down.
200,000
You figure out how long it would take a car traveling at 25 mph
to cover 360 ft. Any driver who does it in less time is speeding.
(25 mi/hr) · (5,280 ft/mile) · (1 hr / 3,600 sec)
= (25 · 5280 / 3600) ft/sec = (36 and 2/3) feet per second.
To cover 360 ft at 25 mph, it would take
360 ft / (36 and 2/3 ft/sec) = 9.82 seconds .
Anybody who covers the 360 feet in less than 9.82 seconds
is moving faster than 25 mph.
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If you're interested, here's how to do it in the other direction:
Let's say a car covers the 360 feet in ' S ' seconds.
What's the speed of the car ?
(360 ft / S sec) · (1 mile / 5280 feet) · (3600 sec/hour)
= (360 · 3600) / (S · 5280) mile/hour
= 245.5 / S miles per hour .
The teacher timed one car crossing both strips in 7.0 seconds.
How fast was that car traveling ?
245.5 / 7.0 = 35.1 miles per hour
Another teacher timed another car that took 9.82 seconds to cross
both strips. How fast was this car traveling ?
245.5 / 9.82 = 25 miles per hour
The answer is 5040 degrees.
