Q. Find the sum of the first 43 terms of the following series, to the nearest integer.4,12,20,…Answer:
Identify Type and Difference: Identify the type of series and the common difference.The given series is arithmetic because there is a constant difference between consecutive terms.To find the common difference, subtract the first term from the second term:12−4=8Common Difference: 8
Find 43rd Term: Find the 43rd term of the series using the formula for the nth term of an arithmetic sequence: an=a1+(n−1)d, where an is the nth term, a1 is the first term, n is the term number, and d is the common difference.a43=4+(43−1)×8a43=4+42×8a43=4+336a43=340
Calculate Sum of 43 Terms: Calculate the sum of the first 43 terms using the formula for the sum of an arithmetic series: Sn=2n∗(a1+an), where Sn is the sum of the first n terms.S43=243∗(4+340)S43=21.5∗344S43=7396