Let speed of the boat in still water = x miles per hour
Let speed of the current = y miles per hour
When water and current both flow in same direction then effective speed will be sum of both speeds that is (x+y)
now plug the given values in formula speed=distance/time
we get equation:
(x+y)=160/8
or x+y=20...(i)
When water and current both flow in opposite direction then effective speed will be difference of both speeds that is (x-y)
now plug the given values in formula speed=distance/time
we get equation:
(x-y)=160/40
or x-y=4
or x=4+y...(ii)
plug value of x into (i)
4+y+y=20
4+2y=20
2y=16
y=8
plug value of y into (ii)
x=4+8=12
Hence final answer is given by:
Speed of the boat in still water = 12 miles per hour
Speed of the current = 8 miles per hour
Answer:
n = 6
Step-by-step explanation:
2 = 
multiply both sides by 3
=> n = 6
X= 9/2, 15/2
decimal form: 4.5,-7.5
mixed number form: 4 1/2, -7 1/2
Answer:
147
Step-by-step explanation:
Since it says need to use 3 to represent pi
well show the formula.
The radius is 7 so we square it, and do the formula.
A=3r²
A=3*49
A=147
