Question

Find the 66th term of the arithmetic sequence -28, -45, -62, ...

Answer 1

To find:

• 66th term of the arithmetic sequence -28, -45, -62, ...

$~$

Solution:

• First term (a) = -28
• Comman difference (d) = -45 - (-28) = - 17
• n = 66

$~$

Using formula:

• ${\sf {\pmb {a_{n} = a + (n -1) × d}}}$

$~$

Substituting values in the formula:

$~$

$\longrightarrow\sf a_{66} = -28 + (66 - 1) × -17$

$\longrightarrow\sf a_{66} = -28 + (65)(-17)$

$\longrightarrow\sf a_{66} = -28 - 1105$

${\longrightarrow \sf {a_{66} = -1133}}$

$~$

Hence,

• 66th term of the arithmetic sequence is -1133.