subject
Mathematics, 10.12.2020 15:20 Ksedro1998

Arithmetic Sequence: original formula: Sn=n/2 (2u1+(n-1)d)

problem formula: S20= 20/2 (2x60 (20-1)(-3)) =630.

The sum of the sequence is 630, but, i need help understanding HOW it is 630. i dont know what to multiply/add/divide in the series first, i don't understand how they got the answer to be 630. Could someone give a detailed explanation on how to work out the problem and parentheses step by step? Thank you

ansver
Answers: 1

Another question on Mathematics

question
Mathematics, 21.06.2019 18:00
Which shows the correct lengths of side c in both scales? scale 1: 45 m; scale 2: 60 m scale 1: 60 m; scale 2: 45 m scale 1: 36 m; scale 2: 27 m scale 1: 27 m; scale 2: 36 m mark this and return save and exit
Answers: 3
question
Mathematics, 21.06.2019 21:40
What is the inverse of the function f(x) = 2x + 1?
Answers: 3
question
Mathematics, 21.06.2019 22:30
Acampus club held a bake sale as a fund raiser, selling coffee, muffins, and bacon and eggs sandwiches. the club members charged $1 for a cup of coffee, 3$ for a muffin , and $4 for a back. and egg sandwich. they sold a total of 55 items , easing $119. of the club members sold 5 more muffins than cups of coffee, how many bacon and egg sandwiches he’s did they sell
Answers: 1
question
Mathematics, 21.06.2019 23:30
Acar loses a quarter of its value every year. it is originally worth $35,000. to the nearest dollar,how much will the car be worth in 8 years?
Answers: 1
You know the right answer?
Arithmetic Sequence: original formula: Sn=n/2 (2u1+(n-1)d)

problem formula: S20= 20/2 (...
Questions
question
History, 12.02.2021 23:50
question
Mathematics, 12.02.2021 23:50
question
Mathematics, 12.02.2021 23:50
question
Mathematics, 12.02.2021 23:50
Questions on the website: 13722360