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Solve for r to find the missing term in geometric sequence


hi can someone please answer my question. thank you ❤️​

Solve for r to find the missing term in geometric sequence — hi can someone please-example-1
User WKPlus
by
2.6k points

2 Answers

28 votes
28 votes

Explanation:

Calcute the ratio :

r = Un/Un-1

r = 60/120

r = ½

Calculate 4th term :

Un = ar^n-1

U4 = 120 × ½^4-1

U4 = 120 × ½³

U4 = 120 × 0.125

U4 = 15

Calculate 5th term :

Un = ar^n-1

U5 = 120 × ½^5-1

U5 = 120 × ½⁴

U5 = 120 × 0.0625

U5 = 7.5

Calculate 6th term :

Un = ar^n-1

U6 = 120 × ½^6-1

U6 = 120 × ½⁵

U6 = 120 × 0.03125

U6 = 3.75

User Aiven
by
2.9k points
10 votes
10 votes

Explanation:

given :

120, 60, 30, _, _, _

find r!

solution :

r = 60/120 = ½.

=> 120,60,30, 15, 15/2 , 15/4 , ...

User Pouya Jabbarisani
by
2.6k points