1.

The average length of 15 wooden sticks is 20 m. If A new plastic stick of a certain length is added in that 15 wooden bunch then average length is increased by 1 m. Find the length of the new plastic stick.1). 21 m2). 34 m3). 45 m4). 36 m

Answer»

Average = (sum of elements)/(NUMBER of elements)

Let the LENGTH of NEW added plastic stick be ‘x' m.

Given,

The average length of 15 wooden sticks is 20 m.

Total length of 15 wooden sticks

= 20 × 15 = 300

Total length of 15 wooden sticks = 300 m

Given,

A new plastic stick of a certain length is added in that 15 wooden bunch then average length is increased by 1 m -

Total length of 15 wooden sticks and 1 plastic stick = (300 + x)m

⇒ New average = 20 + 1 = 21 m

⇒ 21 = (300 + x)/16

⇒ 21 × 16 = 300 + x

⇒ 336 = 300 + x

⇒ x = 36 m

∴ The length of plastic stick is 36 m.


Discussion

No Comment Found