Find the Common Difference of the Sequence $a _ { 1 } = \frac { 9 } { 2 } , a _ { 4 } = \frac { 21 } { 2 } ; \text { find } \mathrm { d }$

question 199

Multiple Choice

Find the common difference of the sequence.
- $a _ { 1 } = \frac { 9 } { 2 } , a _ { 4 } = \frac { 21 } { 2 } ; \text { find } \mathrm { d }$

• A)2
• B) \(\frac { 1 } { 2 }\)
• C)4
• D)6

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