Apleasure boat sets out for a cruise on a river, sailing upstream 24 miles and then turning around and returning to port. the trip upstream requires 144 minutes and the trip downstream requires 40 minutes. find the speed of the boat in still water and the speed of the current in miles per hour (mi/h). round to the nearest whole number.

V(w)  = 26  miles/hour

Step-by-step explanation:

Let  

V(bu)  upstream boat speed         V(w) water speed

Speed upstream

V(bu)  =  24 /144       ⇒   V(b)  =   0,167  miles/min

V(bd)  =  24/40        V(bd)  =  0,6   miles/min

V(bd) =  V(b)  + V(w)

0,6 -0,167  = V(w)

V(w)  = 0,433 miles/min

or equivalent in miles /hour

V(w)  = 25.98 miles/hour

V(w)  = 26  miles/hour

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls

a) y = -3x +2

b) y = 1/2x -6

these 2 can be combined into one equation.

-3x +2 = .5x -6

8 = 3.5x

x = 8 / 3.5 = 2.2857142857

y = -3 * (8 / 3.5) +2

y = (-24 / 3.5) + 2

y = -4.8571428571

step-by-step explanation: