Answer:
Step-by-step explanation:
let wind velocity=x
speed of plane=y
(x+y)*4=808
x+y=808/4=202 ...(1)
(y-x)*4=488
y-x=122 ...(2)
add (1) and (2)
2y=202+122=324
y=324/2=162
from (1)
x+162=202
x=202-162=40
wind velocity=40 m/hr
speed of plane=162 m/hr
I feel it should be 30 because x represents the number of lessons, and 30 is multiplied by that.
Answer:
Solve 3-6x >= 0
6x <= 3
x <= 1/2
Domain: All Real Numbers <= 1/2
Answer:
a = 7
Step-by-step explanation:
I think, what you need to do, is first understand how to find the mean of anything: It's quite simple, actually, just add up all the numbers, then divide that number by the number of numbers. So, let's put it in perspective:
10, 3, 4, a, 6, 9, 10
7 is the mean. 7 is the number of numbers.
If, to find the mean is: 10 + 3 + 4 + a + 6 + 9 + 10= 7a ÷ 7, then: 10 +3 + 4+ 6 + 9 +10= 42
42 plus what divided by 7 is the question now.
42 + a ÷ 7= 7
So, 7 times 7, that's 49 minus 42 and you've got your answer: 7
Answer:
27
Step-by-step explanation:
So first we need to plug in 5 as the variable a and -7 as the variable b
4(5)-(-7)
Next we multiply the 4 and the 5 together to get 20
4(5) = 20 or 4 x 5 = 20
20-(-7)
Now we subtract negative 7 from 20
20-(-7) = 27
This can also be written as 20 plus 7 as a mathematical rule states: two negatives make a positive. So:
20-(-7) = 20 + 7
Both of these are equivalent in every sense of the word and give us our final answer of 27
