UPSC Prelims

Mathematics

Theme:
Sequences and Series / рд╢реНрд░реЗрдгреА рдФрд░ рдЕрдиреБрдХреНрд░рдо

Q70 2019, Sequences and Series

In the sequence 1, 5, 7, 3, 5, 7, 4, 3, 5, 7, how many such 5s are there which are not immediately preceded by 3 but are immediately followed by 7?

рдЕрдиреБрдХреНрд░рдо 1, 5, 7, 3, 5, 7, 4, 3, 5, 7 рдореЗрдВ, рдРрд╕реЗ рдХрд┐рддрдиреЗ 5 рд╣реИрдВ рдЬрд┐рдирдХреЗ рдареАрдХ рдкрд╣рд▓реЗ 3 рдирд╣реАрдВ рд╣реИ рдХрд┐рдиреНрддреБ рдареАрдХ рдмрд╛рдж 7 рд╣реИ.?