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How many two digits number are divisible by 3 |
| Answer» The two -digit numbers divisible by 3 start from 12,15,18,21,...,99Here,\xa0{tex}a=12{/tex}{tex}d=3{/tex}{tex}a_n=a+(n-1)d{/tex}{tex}\\Rightarrow{/tex}\xa0{tex}99=12+(n-1)(3){/tex}{tex}\\Rightarrow{/tex}{tex}\xa099=12+3n-3{/tex}{tex}\\Rightarrow{/tex}\xa0{tex}90=3n{/tex}{tex}\\Rightarrow{/tex}\xa0n=30Thus, 30 two-digit numbers are divisible by 3. | |