Question

The 24th term of an AP is twice its 10th term. Show that its 72nd term is 4 times its 15th term.


Class 10

Arithmetic Progressions

Answer 1

hey mate
here's the solution..

Answer 2

Hey there !!


➡ Given :-

→ a $\tiny 24$ = 2 ( a $\tiny 10$ ).


➡ To prove :-

→ a $\tiny 72$ = 4 ( a $\tiny 15$ ).


➡ Solution :-


we have,

→ a $\tiny 24$ = 2 ( a $\tiny 10$ ).

=> a + 23d = 2( a + 9d ).

=> a + 23d = 2a + 18d.

=> 2a - a = 23d - 18d.

=> a = 5d.


we have, A/Q

a $\tiny 72$ = 4 ( a $\tiny 15$ ).

=> a + 71d = 4 ( a + 14d ).

[ Putting the value of ‘a’ ].

=> 5d + 71d = 4( 5d + 14d ).

=> 76d = 4 × 19d.

$\huge \boxed{ \boxed{ \bf => 76d = 76d. }}$


$\huge \boxed{ \boxed{ \bf{ \mathhbb{ LHS = RHS. }}}}$


✔✔ Hence, it is proved ✅✅.

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THANKS


#BeBrainly.