Answer:
Step-by-step explanation:
Distance upstream = (34-c)(39/60) miles
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Distance downstream = (34+c)(29/60) miles
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Equation:
distance = rate*time
distance up = distance down
(34-c)(39/60) = (34+c)(29/60)
Multiply both sides by 60 to get:
39(34-c) = 29(34+c)
39*34 - 39c = 29*34 + 29c
68c = 340
c = 5 mph speed of the current
Answer: C. 625 and 81
Step-by-step explanation: A relatively prime pair is a pair in which in both numbers given, the only number that can go into each number is one. In 112 and 36, we know 2 can evenly go into each number because they both end in a positive number (112/2 is 56 and 36/2 is 18.) This means A is incorrect. As for B, 11 can evenly go into each number, leaving you with 25 and 7. B is incorrect. And then there's D. 5 can go into each number giving you 160 and 19. D is incorrect.
C is correct because the only numbers that can go evenly into 81 is 1, 3, 9, 27, and 81. None of these numbers, except one can go into 625 also.
Answer:
D. 29.75
Step-by-step explanation:
To determine the mean, you must add up all the numbers and then divide that number by how many numbers you added.
Here,
21 + 23 + 35 + 40
= 119
You added 4 numbers (21, 23, 35, 40),
so, 119 / 4
= 29.75
Hope this helps and a thank won't hurt! :)
Answer:
54 keys
Step-by-step explanation:
If there are 6 keys on each of the nine key rings, you times 6 by 9 to get 54.
Answer:
13 sides.
Step-by-step explanation:
(n - 2) = 1980 / 180 = 11.
n = 13
When the sum of the interior angles is 1980 degrees, the convex polygon will have 13 sides.
i hope this helps and is right! p.s. i really need brainliest :)