The sum of the first n terms in a geometric sequence given the first term (a1) and the common ratio (r) is calculated through the equation,
<span>Sn </span>= (<span><span><span>a1</span>(1−<span>r^n</span>) / (</span><span>1−r)
Substituting the known terms,
Sn = (20)(1 - (1/4)^4)) / (1 - 1/4)
Sn = 26.5625
Thus, the sum of the first four terms is 26.5625. </span></span>
4 - -2
,...........................
9514 1404 393
Answer:
- boat: 48 km/h
- current: 14 km/h
Step-by-step explanation:
The upstream speed is ...
u = (204 km)/(6 h) = 34 km/h
The downstream speed is ...
d = (372 km)/(6 h) = 62 km/h
The speed of the boat in still water is the average of these values:
b = (34 kph +62 kph)/2 = 48 kph
The speed of the water is the difference between the boat's speed and the speed made good:
w = 48 -34 = 14 . . . km/h
The rate of the boat in still water is 48 km/h. The rate of the current is 14 km/h.
Answer:
<h2>0.6 </h2>
Step-by-step explanation:
Each fraction has a equivalent decimal:
So, as you can see, a decimal number between these fraction, could be 0.6, which is equivalent to the fraction 
