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3 years ago

What is a3 of the arithmetic sequence for which a10 is 41 and a15 is 61

1 answer:

3 0

For the arithmetic sequence
a₁, a₂, a₃, ...,
The n-th term is
$a_{n}=a_{1}+(n-1)d$
where d = common difference.

Because a₁₀ = 41,
a₁ + 9d = 41 (1)

Because a₁₅ = 61
a₁ + 14d = 61 (2)

Subtract (1) from (2).
5d = 20
d = 4
From (1), obtain
a₁ = 41 - 9*4 = 5

Therefore
a₃ = 5 + 2*4 = 13

Answer: a₃ = 13

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Divide. Write your answer as a fraction in simplest form. 9/10÷(−6/5)=

bulgar [2K]

Answer:

$-\frac{3}{4}$

Step-by-step explanation:

1. $\frac{9}{10}$ × $-\frac{5}{6}$

2. $-\frac{3}{4}$

3 0

3 years ago

15 players two coaches and 21 parents attend this year sports banquet the cost of each meal was $12 +5% sales tax what was the t

Artist 52 [7]

Answer:

$478.80

Step-by-step explanation:

We have been given that 15 players two coaches and 21 parents attend this year sports banquet the cost of each meal was $12 plus 5% sales tax.

First of all, we will find cost of each meal with tax as:

$\text{Cost of each meal with tax}=\$12+\$12\times \frac{5}{100}$

$\text{Cost of each meal with tax}=\$12+\$12\times 0.05$

$\text{Cost of each meal with tax}=\$12+\$0.6$

$\text{Cost of each meal with tax}=\$12.6$

Now, we will find total persons at the sport banquet as:

$\text{Total persons at banquet}=15+2+21$

$\text{Total persons at banquet}=38$

To find the total cost of food for the banquet, we will multiply cost of food for each person by 38.

$\text{Total cost of food for the banquet}=\$12.6\times 38$

$\text{Total cost of food for the banquet}=\$478.8$

Therefore, the total cost of food for the banquet is $478.80.

5 0

3 years ago

Keegan deposits into her savings account at the beginning of the year. The account earns 3% simple interest each year. She has $

fiasKO [112]

Answer:

She deposits $350 into the account at the beginning of the year.

Step-by-step explanation:

Let us assume that Keegan deposits $P into her savings account at the beginning of the year.

The account earns 3% simple interest each year and she has $360.50 in her account at the end of the year.

If Keegan did not make any additional deposits or withdrawals during the year.

So, we can write that $P[1+\frac{3}{100} ]= 360.50$

⇒ P = $350 (Answer)

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3 years ago

Five expressions that are equivalent to 20x + 18

jonny [76]

1) 10x + 9

2) 40x + 36

3) 60x + 54

4) 80x + 72

5) 100x + 90

7 0

3 years ago

4x+3=-5 helppp please

Goryan [66]

Answer: x = -2

Step-by-step explanation: To solve for x, in the equation you see here, our goal is to get x by itself.

Our first step will be to isolate the term containing x which in this case is 4x. To isolate 4x, we have to get rid of the +3 by subtracting 3 from both sides of the equation. On the left, +3 and -3 cancel out and we're left with 4x. On the right, -5 - 3 simplifies to -8.

Now we have the equation 4x = -8.

To get x by itself, we divide both sides of the equation by 4. On the left, the 4's cancel and on the right, -8 divided by 3 is -2 so x = -2

5 0

3 years ago

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