Question

There are 25 trees at equal distance of 5 metres in a line with a well, the distance of the well from the nearest tree being 10 metres. a gardener waters all the tree separately starting from the well and he returns to the well after watering each tree to get water for the next. find the total distance the gardener will cover in the order to water all the trees.

Answer 1

Solution :-

Equal distance means this forms an A.P

Since he goes 5 m and returns same

$\therefore$ Distance travelled by him = 10 m

Similarly he will travel 20 for second 30 for third

upto 25 plants

we need to find total sum i.e., distance

$\therefore S=\frac{25}{2}[2\times 10+(25-1)\times 10]$

where S = total distance

$\therefore S=\frac{25}{2}[20+240]=3250m$