In a row of $35$ children,$M$ is $15^{th}$ from the right end and there are $10$ children between $M$ and $R.$ What is $R$'s position from the left end of the row?

Sanal's position in a row is $12^{th}$ from the front side and $47^{th}$ from the back side. How many persons are standing in that row?

The train for Lucknow leaves every two and a half hours from New Delhi Railway Station. An announcement was made at the station that the train for Lucknow had left $40 \,minutes$ ago and the next train will leave at $18:00 \,hrs.$ At what time was the announcement made?

In the sequence $5, 1, 4, 7, 3, 9, 8, 5, 7, 2, 6, 3, 1, 5, 8, 6, 3, 8, 5, 2, 2, 4, 3, 4, 9, 6$,how many even numbers are there which are immediately preceded by an odd number and immediately followed by an even number?

$A$ monkey climbs $30$ feet at the beginning of each hour and rests for a while,during which he slips back $20$ feet before he again starts climbing at the beginning of the next hour. If he begins his ascent at $8:00 \, a.m.$,at what time will he first touch a flag at $120$ feet from the ground?

In the series,$6, 4, 1, 2, 2, 8, 7, 4, 2, 1, 5, 3, 8, 6, 2, 1, 7, 1, 4, 1, 3, 2, 8, 6$,how many pairs of successive numbers have a difference of $2$ each?