Answer:
Vp = 1 / 24 miles/min the speed in still water
Step-by-step explanation:
Lets call Vp speed of swimmer and Vw speed of water then:
Downstream Vp + Vw
Swimmer does 2 miles in 40 minutes then he does
1 mile in 20 minutes
Upstream Vp - Vw
Swimmer does 2 miles in 60 minutes then he does
1 mile in 30 minutes
We get the following system:
(Vp + Vw )* 20 = 1 (1) and
( Vp - Vw )* 30 = 1 (2)
Solving the system
From equation (1)
20*Vp + 20* Vw = 1 ⇒ Vw = ( 1 - 20*Vp ) /20
Plugging that value in the second equation
(Vp - Vw )* 30 = 1 ⇒ [ Vp - ( 1 - 20*Vp )/20 ] * 30 = 1
[20*Vp - 1 + 20*Vp ] * 30/20 = 1 ⇒ [ 40*Vp - 1 ] *30 = 20 or
[ 40*Vp - 1 ] *3 = 2
120* Vp - 3 = 2 ⇒ 120*Vp = 5 and Vw = 1 /120 miles/min
Vp = 5 / 120 miles/min or
Vp = 1 / 24 miles/min
and speed of water Vw = 1 / 120
<span>Y=log xIf y=10, then what is x? 1</span>
Answer:
13 and 11
Step-by-step explanation:
13+11=24
13-11=2
Answer:
24.1 x 10^4 = 241000 .056 x 10^7 = 560000 507 x 10^-5 = 0.00507
Step-by-step explanation:
for scientific notation, all you need to do is start at the decimal point (or end of whole number) and move over the amount of spaces (the exponent) to the right. if it is a negative exponent, instead of moving to the right, you should move to the left.
for example : 500 x 10^3
when you start from the last zero and move to the right, you need to fill the space with three zeroes.
so 500 x 10^3 = 500,000.
