Question

lf the everage height of 20 girls in the class is 130cm and the everage height 20 boys is 134cm,what is the everage height of all the students in the class A(132.5cm) B( 133cm) C(132 cm)D(131.5cm)​

Answer 1

Answer:

The average height of all students is

=(130+134)/2

=264/2

=132cm

Answer 2

$\Large{\bf{\green{\mathfrak{\dag{\underline{\underline{Given:-}}}}}}}$

• Aeverage height of 20 girls in the class is 130cm and the aeverage height 20 boys is 134cm.

$\Large{\bf{\orange{\mathfrak{\dag{\underline{\underline{To \: Find:-}}}}}}}$

• Average height of all the students.

$\Large{\bf{\red{\mathfrak{\dag{\underline{\underline{Solution:-}}}}}}}$

• Average height of 20 girls = 130 cm

• Average height of 20 boys = 134 cm

• Average height of the class =

$\boxed{\pink{\sf Average \: height \: of \: the \: class \: = \: \dfrac{Average \: height \: of \: boys \: + \: Average \: height \: of \: girls}{2}}}$

Substituting the values,

$\sf Average \: height \: of \: the \: class \: = \: \dfrac{134 \: + \: 130}{2}$

$\sf Average \: height \: of \: the \: class \: = \: \dfrac{264}{2}$

$\sf Average \: height \: of \: the \: class \: = \: \dfrac{\cancel{264}}{\cancel{2}}$

$\sf Average \: height \: of \: the \: class \: = \: 132 \: cm$

Therefore,

• $\underline{\boxed{\therefore{\purple{\frak{Average \: height \: of \: the \: class \: = \: 132 \: cm.}}}}}$

• $\underline{\boxed{\therefore{\blue{\frak{Option \: (C) \: 132 \: cm \: is \: the \: correct \: answer. }}}}}$