The number of common terms in the progressions
$4,9,14,19, \ldots \ldots$, up to $25^{\text {th }}$ term and
$3,6,9,12, \ldots \ldots$, up to $37^{\text {th }}$ term is :
Solution
<p>$4,9,14,19, \ldots$, up to $25^{\text {th }}$ term</p>
<p>$\mathrm{T}_{25}=4+(25-1) 5=4+120=124$</p>
<p>$3,6,9,12, \ldots$, up to $37^{\text {th }}$ term</p>
<p>$\mathrm{T}_{37}=3+(37-1) 3=3+108=111$</p>
<p>Common difference of $\mathrm{I}^{\text {st }}$ series $\mathrm{d}_1=5$</p>
<p>Common difference of $\mathrm{II}^{\text {nd }}$ series $\mathrm{d}_2=3$</p>
<p>First common term $=9$, and their common difference $=15\left(\operatorname{LCM}\right.$ of $\mathrm{d}_1$ and $\left.\mathrm{d}_2\right)$ then common terms are $9,24,39,54,69,84,99$</p>
About this question
Subject: Mathematics · Chapter: Sequences and Series · Topic: Arithmetic Progression
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