Speed, S = Distance (d) / Time (t) => S= d/t => t= d/S
Let the speed of boat in still water be x mph
Resulting speed upstream = x-4 mph for a distance of 30 miles
Resulting speed downstream = x-4 mph for a distance of 50 miles
Time taken in both distances is equal.
Therefore,
30/(x-4) = 50/(x+4) => 30(x+4) = 50(x-4) => 30x+120 = 50x-200 => 120+200 = (50-30)x => 20x = 320 => x=320/20 = 16 mph
The speed of boat in still water is 16 mph.
Answer:
10.1%
Step-by-step explanation:
The first thing we should do is calculate the total volume of the solution when mixing them would be:
0.7 + 0.3 = 1
Now, we have that the resulting concentration (x) would be equal to the sum of the multiplications between the volumes and the concentrations to be mixed, as follows:
x * 1 = 0.7 * 0.05 + 0.3 * 0.22
x = 0.035 + 0.066
x = 0.101
That is, the concentration of the resulting mixture would be 10.1% (0.101 * 100)
1/2 is equivalent to 50%
3/4 is equivalent to 75%
75% > 50% (75% is larger than 50%)
75% = 3/4
The answer is 3/4
Hope the answer helps :)
Commutative law: a+b=b+a thats it...
So 9+7 can also be written as 7+9=16
X=14
2x=28
4x-9=47
you solve for x after you add all the sides