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>
Answer:
5000/750 = 20:3
Step-by-step explanation:
5kg = 5000g
5000:750 (divide by 10)
500:75 (divide by 5)
100:15 (divide by 5)
20:3
Answer:
56
Step-by-step explanation:
Complete question:
Z varies jointly with x and y , x=2 and y=2, z=7. Find z when x=4 and y=8 using joint variation . (I need the problem worked out step by step)
If z varies jointly with x, and y, this is expressed as;
z = kxy
If z=7 when x= 2, y= 2
7 = k(2)(2)
7 = 4k
k = 7/4
To get z when x= 4 and y = 8
z = kxy
z =7/4 (4)(8)
z = 7*8
z = 56
Hence the value of z is 56
