Question

Find the 30th term of the AP 10,7,4........
In this question, can you expline how we get the common difference.?

Answer 1

Answer:

-77 (common difference means the difference between 2 consecutive terms or constant)

Step-by-step explanation:

Let a be the first term

n be the no. of terms

d be the difference

The formula for A.P. = a + (n - 1)d

a = 10

n = 30

d = -3(as it is descending)

a + (n - 1)d

10 + (30 - 1)*(-3)

10 + (-87)

10 - 87

-77

Conclusion

∴ the 30th term is -77

Hope you understood :)

Answer 2

$\huge\underline\mathbb{\red S\pink{O}\purple{L} \blue{UT} \orange{I}\green{ON :}}</p><p>$

★ Given that,

Find the 30th term of an AP: 10,7,4...

★ Let,

• a1 = 10
• a2 = 7
• a3 = 4

To find the common difference (d) of an AP, subtract a2 - a1 & a3 - a2.

↪ a2 - a1 = 7 - 10 = - 3

↪ a3 - a2 = 4 - 7 = - 3

Therefore, the common difference (d) is constant.

Hence, we can find out like this.

★ To find,

• 30th term of AP.

By using nth term formula...

☯ an = a + (n - 1)d

• a = 10
• d = - 3
• n = 30

➡ a30 = 10 + (30 - 1)(-3)

➡ a30 = 10 + 29(-3)

➡ a30 = 10 - 87

➡ a30 = - 77

$\underline{\boxed{\bf{\purple{ ∴ Hence\;30th\;term\;of\;an\;AP\;is\;“\;-77\;”}}}}$

Step-by-step explanation:

$<marquee behaviour-move><font color="green pink"><h2># PLEASE MARK ME AS BRAINLIEST✌✌✌</ ht></marquee>$