Step-by-step explanation:
a2 = a1×r
a3 = a1×r²
a1×r + a1×r² = 6×a4 = 6×a1×r³
1.
r + r² = 6r³
6r³ - r² - r = 0
r×(6r² - r - 1) = 0
the first solution is obvious : r = 0.
but this is no useful ratio for a geometric sequence.
the other 2 solutions are in
6r² - r - 1 = 0
the general solutions for a quadratic equation are
(-b ± sqrt(b² - 4ac))/(2a)
in our case
a = 6
b = -1
c = -1
so,
(1 ± sqrt(1 - 4×6×-1))/12
r = (1 ± sqrt(25))/12
r = (1 ± 5)/12
r1 = (1+5)/12 = 6/12 = 1/2
r2 = (1-5)/12 = -4/12 = -1/3
2.
we can ignore r2 (negative) and just focus on r1 (1/2).
the second term is 8. that means
a2 = 8 = a1×r = a1×1/2
a1 = 2×a2 = 16
so, we have
a1 = 16
a2 = 8
a3 = a2×1/2 = 8×1/2 = 4
a4 = a3×1/2 = 4×1/2 = 2
a5 = a4×1/2 = 2×1/2 = 1
a6 = a5×1/2 = 1×1/2 = 1/2
a7 = a6×1/2 = 1/2 × 1/2 = 1/4
Answer:At a charity fund raiser , adult tickets were sold for 8$ children each and children’s tickets were sold at 2$ each. write an algebraic expression for the total amount raised from the sale of tickets. At a charity fund raiser , adult tickets were sold for 8$ children each and children’s tickets were sold at 2$ each. write an algebraic expression for the total amount raised from the sale of tickets. How much money was raised if the fundraiser sold 238 adult tickets and 375 children’s tickets?
Step-by-step explanation:
2,654$
Step-by-step explanation:
8a + 2c
8 x 238 = 1,904
2 x 375 = 750
750 + 1,904 = 2,654
2,654$
Answer:
C.(3 × $5) + $1 + $3 = x
Step-by-step explanation:
3x9=15($15 for pens)
$1 for pencils
$3 (for paper)
so (3 × $5) + $1 + $3 = x
hope this helps! C:
Answer:
n ≤ -7
Step-by-step explanation:
Sum of 15 and n is less than or equal to 8.
15 + n ≤ 8
Collect like terms
n ≤ 8 – 15
n ≤ -7
<span>Experimental probability is defined as the
ratio of the number of times an event occurs to the total number of
trials the activity is performed
In this case the number that the event occurred is 8 and the number of trials is 50, so the ratio is 8/50 = 4/25.
Then the answer is option B: 4/25
</span>
