Answer:
2,57 * 10^5 or 257000
Step-by-step explanation:
(5,14 * 10^9) / (2 * 10^4) =
2,57 * 10^5 =
257000
#64
Let x represent the time spent for valleyball
Then swimming will be 2x
x + 2x = 4.5
3x = 4.5
x = 4.5/3
x = 1.5
Time spent on valleyball: 1 1/2 hours
Time spent on swimming: 3 hours
Answer:
$26.50
Step-by-step explanation:
7.95/3=2.65
2.65*10=26.5
Answer:
0
Step-by-step explanation:
Numbers on balls:
1, 4, 7, 7, 8
Try to find the sum of all numbers:
1+4+7+7+8 = 27
According to the rule of 3, any number is dividable by 3 if the sum of it's individual is divided by 3.
27 is dividable by 3, therefore any combination will result a number with a factor of three.
Prime number is the number that is only dividable by 1 and itself. Therefore, any combination using those numbers are not prime number.
So the probability is 0
Answer: the speed of the current is 9 mph.
Step-by-step explanation:
Let x represent the speed of the current.
A boat can travel 21 mph in still water. If it travels 270 miles with the current. It means that the total speed with which the boat travelled with the current is (21 + x) mph.
Time = distance/speed
Time spent by the boat in travelling 270 miles is
270/(21 + x)
In the same length of time, it travels 108 miles against the current. It means that the total speed with which the boat travelled against the current is (21 - x) mph.
Time = distance/speed
Time spent by the boat in travelling 108 miles is
108/(21 - x)
Since the time is the same, then
270/(21 + x) = 108/(21 - x)
270(21 - x) = 108(21 + x)
5670 - 270x = 2268 - 108x
108x + 270x = 5670 - 2268
378x = 3402
x = 3402/378
x = 9
