Find the natural number from 101to 999 which are divisible by 2 and 5

1.	Find the natural number from 101to 999 which are divisible by 2 and 5
Answer» Natural numbers between 101 and 999 divisible by both 2 and 5, i.e., divisible by L.C.M of 2 and 5 i.e., 10, are 110, 120, 130 ,...., 990.so, this forms an AP 110,120....,990., where first term({tex}a{/tex})=110 and common difference({tex}d{/tex})=120-110=10, and last term({tex}l{/tex})=990Let {tex}l = {a_n} = a + (n - 1)d{/tex}Then,\xa0{tex}990 = 110 + (n - 1) \\times 10{/tex}{tex} \\Rightarrow n = 89{/tex}

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