Let the boat speed in still water be b.
Let the current speed be c.
The speed going upstream is 20/4 = 5 mph.
The speed going downstream is 32/4 = 8 mph.
b - c = 5 ........(1)
b + c = 8 .......(2)
Adding equations (1) and (2) we get:
2b = 13
b = 13/2 = 6.5
Plugging in the value for b into equation (1) we find c = 1.5.
The boat speed in still water is 6.5 mph and the current speed is 1.5 mph.
The plumber worked for 5 hours because 450-200=250 which gets rid of the initial fee so 250 divided by 50 is 5
1 people eat 3/8 pound of potato salad lets reoresent it：
x=3/8
Lets say n is the value of how many people ate with 7 people
7x=n
now substitute
7x=n
7(3/8)=n
21/8=n
n=2 5/8
Answer:
DEC+DEF=180
DEC=180-116
DEC=64°
in triangle DCE
angle D+angle C+angle E=180
7y+6+4y+64=180
11y+70=180
11y=180-70
11y=110
y=110/11
y=10°
angle C=4y
=4(10)
=40°
So since they are similar
AC/BC=CD/CE
so
(66-x)/30=(x+4)/5
times both sides by 5
(66-x)/6=x+4
times both sides by 6
66-x=6(x+4)
distribute
66-x=6x+24
add x to both sides
66=7x+24
minus 24 from both sides
42=7x
divide both sides by 7
6=x
x=6 units
