Mathematics, 21.06.2019 17:00 landenDfisher

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Answers: 2

Show answers

Answers

Answer from: ineedhelp2285

1) For an 10 month period, the last term is 10 and the series sum is 55.

2) For a 15 month period, the last term is 15 and the series sum is 120.

3) For a 20 month period, the last term is 20 and the series sum is 210.

Step-by-step explanation:

Given : For the Rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78.

To find :

1) For an 10 month period, the last term is__ and the series sum is__ .

2) For a 15 month period, the last term is __ and the series sum is .

3) For a 20 month period, the last term is__ and the series sum is__ .

Solution :

For the Rule of 78, for a 12 month period, the last term in the sequence is 12 and the series sums to 78. It is also defined as,

1+2+3+4+5+6+7+8+9+10+11+12=78

It is an AP with first term 1 and common difference 1.

The formula for sum of n terms is,

$S_n=\frac{n}{2}[a+l]$

Where, a is the first term and l is the last term

1) For an 10 month period, the last term is__ and the series sum is__ .

For an 10 month period, the last term is 10.

$S_{10}=\frac{10}{2}[1+10]$

$S_{10}=5[11]$

$S_{10}=55$

2) For a 15 month period, the last term is __ and the series sum is .

For an 15 month period, the last term is 15.

$S_{15}=\frac{15}{2}[1+15]$

$S_{15}=7.5[16]$

$S_{15}=120$

3) For a 20 month period, the last term is__ and the series sum is__ .

For an 20 month period, the last term is 20.

$S_{20}=\frac{20}{2}[1+20]$

$S_{20}=10[21]$

$S_{20}=210$

Answer from: smelcher3900

Can u answer my question

Answer from: stopithelpmeplease

Step-by-step explanation:

The formula for determining the nth term of an arithmetic sequence is expressed as

Sn = n/2(a + l)

Confirming the rule of 78, the last term is 12 and the first term is 1. Therefore

78 = 12/2(1 + 12)

78 = 6(1 + 12)

78 = 6 + 72

For a 10 month period, the last term is 10, the sum of the series, S10 is

S10 = 10/2(1 + 10)

S10 = 5 × 11 = 55

For a 15 month period, the last term is 15, the sum of the series, S15 is

S15 = 15/2(1 + 15)

S15 = 7.5 × 16 = 120

For a 20 month period, the last term is 20, the sum of the series, S20 is

S20 = 20/2(1 + 20)

S20 = 10 × 21 = 210

Answer from: newjersey4015

For a 10 month period the last term is 10 and the series sum is 55. For a 15 month period the last term is 15 and the sum is 120. For a 20 month period the last term is 20.
If u want the sum then it is 210.

Hope this helps you!

Another question on Mathematics

Mathematics, 21.06.2019 14:30

Mr switzer needs to buy new 1-foot tiles to cover his bathroom floor. the floor is 12 feet long and 8 feet wide. each square foot of tile will cost $1.79. in dollars what will be the total cost of the tiles he needs to buy.

Answers: 3

Answer

Mathematics, 21.06.2019 20:30

Linda loans her friend $250 with a 5% monthly intrest rate. how much was the whole loan?

Answers: 1

Answer

Mathematics, 21.06.2019 21:00

What is the missing statement in step 4? ? rts ? ? vtu and ? rtu ? ? vts ? rts ? ? rvs and ? rtu ? ? stv ? vrs ? ? vru and ? usr ? ? usv ? vur ? ? vus and ? uvs ? ? sru

Answers: 3

Answer

Mathematics, 22.06.2019 02:00

Tanyss's house has 25 windows. her brother has washed 22 of the windows. what percent of the windows has her brother washed?

Answers: 1

Answer

You know the right answer?

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums t...

Questions