I do not see anything wrong with it
10t = b - 4
12b+8t = $348
This is a system of equations. I’ll be solving through substitution.
In the first equation. solving for b (the easier variable to isolate) gives you:
b = 10t + 4
Substitute this into the second equation:
12(10t+4) +8t = 348
120t+48+8t = 348
128t = 300
t = 2.34375 —> round it to the nearest cent to get 2.34 dollars
b = 10t+4
b = 10(2.34)+4
b = 27.4 dollars
All three series converge, so the answer is D.
The common ratios for each sequence are (I) -1/9, (II) -1/10, and (III) -1/3.
Consider a geometric sequence with the first term <em>a</em> and common ratio |<em>r</em>| < 1. Then the <em>n</em>-th partial sum (the sum of the first <em>n</em> terms) of the sequence is
Multiply both sides by <em>r</em> :
Subtract the latter sum from the first, which eliminates all but the first and last terms:
Solve for :
Then as gets arbitrarily large, the term will converge to 0, leaving us with
So the given series converge to
(I) -243/(1 + 1/9) = -2187/10
(II) -1.1/(1 + 1/10) = -1
(III) 27/(1 + 1/3) = 18
During 7 hours: 28 parts assembled
during 14 hours: 56 parts assembled
during 21 hours: 84 parts assembled
during 28 hours: 112 parts assembled
during 35 hours: 140 parts assembled