Answer:
The velocity of jet in still air is
and velocity of wind is
.
Step-by-step explanation:
Let x be the rate of the jet in still air and y be the rate of the wind.
Given:
Velocity against wind, a jet travels 2160 miles in 3 hours.
Velocity against wind 
Flying with the wind, same jet travels 6000 miles in 6 hours.
Flying with the wind 
As such its velocity against wind is 
and with wind is
therefore
------------(1)
---------------(2)
Adding equation 1 and 2.



Put x value in equation 2



Hence velocity of jet in still air is
and velocity of wind is
.
Answer:

Step-by-step explanation:
You can understand the statement from many perspectives, but in terms of proposition logic it is best to understand it as "negation of a" or " b" in mathematical terms is written like this

You can show that they are logically equivalent because they have the same truth table.
In this question, the speed of the dolphin is already given, but the unit is different. The speed of the dolphin is given as 40 miles per hour and it has to be converted to feet per hour.
We already know that 1 mile = 5280 feet
Then
40 mile = 5280 * 40 feet
= 211200 feet
So the speed in feet per hour will be 211200 feet per hour. I hope the procedure is clear enough for you to understand. You can always use this method for solving similar problems without requiring any help from outside.
Answer:
$1756
Step-by-step explanation:
1. More = Addition
2. Twice = Multiplication by 2
3. Tuition costs $100 more than twice room and board
Tuition = 2x + 100
$2584 = (2x + 100) + x
$2584 = 3x + 100
4. Subtract 100 on both sides: $2484 = 3x
5. Divide both sides by 3: $828 = x
6. Plug it in to the tuition equation: Tuition = 2(828) + 100
= $1756
Check Work: (828*2) + 100 = $1756
$1756 + 828 = $2584