Question

a theif after committing a theft runs at a uniform speed of 50m/min.after 2 min a policeman runs to catch him.he goes 60m in first min and <br />increase his speed by 5m/min every succeeding min.after how many minutes,the police man will catch the theif? <br />it's urgent, give me fast solution....​

Answer 1

Answer:

Step-by-step explanation:

let time = x

a=60 d = -5

Sn = x/2 [ a+{x-1}d]

x/2 [60+{x-1}5]

x/2 [60+5x-5]

60x/2 + 5x2/2 [square hai yeh] - 5x/2

[60x + 5x2 -5x] / 2

[55x +5x2 ]/2

solve this eqn u wil get the ans