P = pizza and c =cakes
Last week: 8p + 13c = 134
Today: 28p + 4c = 220
Let’s take the formula for today and subtract 28p from each side to isolate the 4c.
4c = 220 - 28p
Now divide each side by 4
c = (220 - 28p)/4
Simplify to c = 55 - 7p
Now go to the formula for last week, substitute the c for 55-7p
8p + 13(55 - 7p) = 134
8p + 715 - 91p = 134
Simplify to 715 - 83p = 134
Let’s add 83p to each side.
715 = 134 + 83p
Subtract 134 from each side
581 = 83p
Divide each side by 83
p = $7
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.
Answer:
30,114.3%
Step-by-step explanation:
Use the percent increase formula:
((new value - initial value) / initial value) x 100
Plug in the values:
((211,500 - 700) / 700) x 100
(210,800 / 700) x 100
= 30,114.29
So, the percent increase is 30,114.3%