Question

Which term of the arithmetic progression 5, 15, 25,will be 140 more than 31st term?​

Answer 1

       Answer:

          60th term

Step-by-step explanation:-

AP = 5 , 15 , 25

a = 5 ,  d = 15 - 5 = 10 ,

with n = 31

an = a + d(n - 1)

    = 5 + 15(31 - 1)

    = 5 + (15 * 30)

    = 5 + 450

an = 455

am = 455 + 140

am = 595

am = a + d(m - 1)

595 = 5 + 10(m - 1)

595 - 5 = 10(m - 1)

10(m - 1) = 590

m - 1 = 590 / 10

m - 1 = 59

m = 60

∴ the 60th term will be 140 more than 31st term

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