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
Answer:
First let's define what modular arithmetic is, what would come is an arithmetic system for equivalence classes of whole numbers called congruence classes.
Now, the modular division is the division in modular arithmetic.
Answering the question, a modular division problem like ordinary arithmetic is not used, division by 0 is undefined. For example, 6/0 is not allowed. In modular arithmetic, not only 6/0 is not allowed, but 6/12 under module 6 is also not allowed. The reason is that 12 is congruent with 0 when the module is 6.
14.29 * .0725 = 1.04
1.04 * 3 = 3.12
First find the amount of tax by multiplying 21 × 8.5%.
.085 × 21 = 1.785 = 1.79 (rounded)
Now add the tax back into the price...
21 + 1.79 = $22.79
