Question

Haji rows his canoe 10 mph in still water. He noticed one day that he could row 4 miles upstream in the same amount of time he could row 6 miles downstream. What was the approximate speed of the current that day?
2.0 mph
3.3 mph
5.0 mph
10.0 mph

Answer 1

Answer : 2.0 mph

Haji rows his canoe 10 mph in still water

Speed of still water = 10 mph

Let the speed of the current = x

Upstream speed = 10 - x

Downstream speed = 10+x

Upstream Distance = 4 miles

Downstream Distance =  6 miles

$Time = \frac{Distance}{speed}$

Time taken on upstream =  $\frac{4}{10-x}$

Time taken on downstream =  $\frac{6}{10+x}$

Same time taken for both upstream and downstream

So $\frac{4}{10-x} = \frac{6}{10+x}$

Cross multiply it

4(10+x) = 6(10-x)

40 + 4x = 60 -6x

Add 6x  and subtract 40 on both sides

10x = 20 (divide by 10)

x= 2

So speed of the current = 2.0 mph

Answer 2

The approximate speed of the current that day is 2.0 mph.\

The correct option is A.

Given

The speeds of the current = x

Upstream speed = 10 - x

Downstream speed = 10+x

Upstream Distance = 4 miles

Downstream Distance =  6 miles

What is speed?

Speed is defined as the fraction of the total distance and time taken to complete it.

The following formula is used to calculate speed;

$\rm Speed =\dfrac{Distance}{Time}$

Therefore,

The approximate speed of the current that day is;

$\rm = \dfrac{Upstream \ distaance}{Upstream \ speed}= \dfrac{downstream \ distaance}{downstream \ speed}\\\\ \dfrac{4}{10-x}=\dfrac{6}{10+x}\\\\4(10+x)=6(10-x)\\\\40+4x=60-6x\\\\4x+6x=60-40\\\\10x=20\\\\x= \dfrac{20}{10}\\\\x=2$

Hence, the approximate speed of the current that day is 2.0 mph.

To know more about Speed click the link given below.

https://brainly.com/question/7430699