On a windy day william found that he could travel 10 mi downstream and then 2 mi back
upstream at top speed in a total of 16 min. what was the top speed of william's boat if the rate
of the current was 30 mph? (let x represent the rate of the boat in still water.)

The top speed of William's boat was 45 mph

Step-by-step explanation:

Let

x -----> represent the rate of the boat in still water in mph

we know that

The speed or rate is equal to divide the distance by the time

speed=distance /time

time=distance/speed

Downstream

speed=(30+x) mph

distance=10 mi

time1=10/(30+x)

Upstream

speed=(x-30) mph

distance=2 mi

time2=2/(x-30)

The sum of the time downstream plus the time upstream must be equal to 16 minutes

Convert minutes to hours

Multiply by (x+30)(x-30) both sides

Multiply by 60 both sides

Divide by 16 both sides

The solution is x=45\ mph

Option 2,3 and 4. Step-by-step explanation: Ratio and proportion  are complementary. Proportions are made from ratios. Option 2 is correct that is Corresponding dimensions must be in same position in the ratios. Option 3 is correct  two ratios in the proportion are equal Option 4 is correct that is enlargement or reduction is proportional to the original figure

Step-by-step explanation:

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