$\"\"$

\

The given values are $\"\"$ .

\

Where $\"\"$ is the first term and $\"\"$ is the common difference.

\

The sum of an arithmetic series $\"\"$ .

\

$\"\"$ (Substitute $\"\"$ )

\

$\"\"$ (Add: $\"\"$ ) $\"\"$

\

Apply multiplication property of equality: a = b then $\"\"$ .

\

$\"\"$ (Multiply each side by 2)

\

$\"\"$ (Cancel common terms)

\

$\"\"$ (Multiply: $\"\"$ )

\

Apply division property of equality: a = b then $\"\"$ .

\

$\"\"$ (Divide each side by 414)

\

$\"\"$ (Cancel common terms)

\

$\"\"$ (Divide: $\"\"$ ) $\"\"$

\

Apply nth term of the arithmetic sequence formula: $\"\"$ .

\

$\"\"$ (Substitute $\"\"$ )

\

$\"\"$ (Subtract: $\"\"$ )

\

Apply addition property of equality: a = b then $\"\"$ .

\

$\"\"$ (Add 13 to each side)

\

$\"\"$ (Apply additive inverse property: $\"\"$ )

\

$\"\"$ (Apply additive identity property: $\"\"$ )

\

$\"\"$ (Add: 427 + 13 = 440) $\"\"$

\

Apply division property of equality: a = b then $\"\"$ .

\

$\"\"$ (Divide each side by 88)

\

$\"\"$ (Cancel common terms)

\

d = 5 (Divide: $\"\"$ )

\

The 1st term is $\"\"$ , 2nd term is $\"\"$ ,

\

3rd term is $\"\"$ , $\"\"$

\

The first three terms of the arithmetic series is $\"\"$ .