Q. What is the next term of the geometric sequence?20,−10,5,
Identify sequence type: Identify the type of sequence.The given sequence is 20, −10, 5, which changes sign and magnitude. This indicates that it is a geometric sequence because each term is multiplied by a common ratio to get the next term.
Determine common ratio: Determine the common ratio of the sequence.To find the common ratio, divide the second term by the first term: −2010=−21. Then, check this ratio by dividing the third term by the second term: −105=−21. Since the ratio is consistent, the common ratio is −21.
Calculate next term: Calculate the next term in the sequence.To find the next term, multiply the last known term by the common ratio: 5×(−21)=−2.5.