Correct Question
30th term of AP 10, 7, 4 is
Answer:
The 30th term is -77
Explanation:
Required
Determine the 30th term of the given progression
First, we need to determine the common difference (d);
![d = T_2 - T_1](https://img.qammunity.org/2021/formulas/mathematics/high-school/mu36fx69cglap6hxpdoecr7z803rh0ixd9.png)
![d = 7 - 10](https://img.qammunity.org/2021/formulas/mathematics/high-school/8svq4yrybbo7187m8a5rgic3z1zbkplvr4.png)
![d = -3](https://img.qammunity.org/2021/formulas/mathematics/college/mzwi4va81j68o5x6iwztfs9tjh5w2vranr.png)
The nth term of an AP is calculated by
![T_n = a+ (n -1) d](https://img.qammunity.org/2021/formulas/mathematics/high-school/19pnenn6r7mr8yxiig4mpxv4l7g67knz3r.png)
In this case;
n = 30;
a = First term = 10
d = -2
Substitute these values in the given formula
![T_(30) = 10+ (30 -1) * -3](https://img.qammunity.org/2021/formulas/mathematics/high-school/sbv6gxsrusyqujmggvo6zd0y3fwoq2wrtp.png)
![T_(30) = 10+ (29) * -3](https://img.qammunity.org/2021/formulas/mathematics/high-school/y7gjo3ljuunj5ftaggir1567ob5dm3tb9k.png)
Open the bracket
![T_(30) = 10-87](https://img.qammunity.org/2021/formulas/mathematics/high-school/nk88z37072pksfkvfoyw6bkee76mi8n1lu.png)
![T_(30) = -77](https://img.qammunity.org/2021/formulas/mathematics/high-school/dtfjcd9ez6q06a0umysot93e8lcyy67gn9.png)
Hence, the 30th term is -77