Question

The 5th and 10th terms of an AP are 36 and 61 respectively. Find the AP and its 15th term.

Answer 1

Answer:

AP = 16,21,26,31

15th term = 86

Step-by-step explanation:

Answer 2

Answer:

15'TH TERM = 86

Step-by-step explanation:

HAVE TO FIND THE 15'TH TERM OF AN AP

WE HAVE 5'TH TERM = 36

                10'TH TERM = 61

5'TH TERM MEANS      A+4D=36------------>(1)

10'TH TERM MEND      A+9D=61------------->(2)

SOLVE THE FOLLOWING EQUATION (1)&(2),WE GET

                          A+4D=36

                          A+9D=61

                            -5D=-25

                               ⇒D=5

PUT D IN EQN (1) OR (2) TO FIND A

             A+4D=36------->(1)

             A+20=36

             ⇒A=16

15'TH TERM = A+14D

                     = 16+14×5

                     = 16+70

⇒15'TH TERM     =86

HOPE IT CLEAR AND HELP FULL