Average weight of A , B and C is 45, kg . If average weight of A and B is 40 ,kg and that of B and C

English

Gujarati

Hindi

4.Average

hard

The average weight of $A , B$ and $C$ is $45\, kg$. If the average weight of $A$ and $B$ is $40 \,kg$ and that of $B$ and $C$ is $43\, kg$, then the weight of $B$ is

A

$17$

B

$20$

C

$26$

D

$31$

Solution

Weight of $A+B+C=45 \times 3=135 kg$…..$(1)$

Weight of $A+B=40 \times 2=80 kg$…..$(2)$

Weight of $B + C =43 \times 2=86 kg$…..$(3)$

Subtracting (2) from (1),

Weight of $C=135-80=55 kg$…..$(4)$

Subtracting (3) from (1),

Weight of $A=135-86=49$ kg…..$(5)$

Subtracting (5) from (2),

Weight of $B=80-49=31 kg$…..$(6)$

Standard 13

Quantitative Aptitude

Share

Similar Questions

In a $20$ over match, the required run rate to win is $7.2 .$ If the run rate is $6$ at the end of the $15^{th}$ over, the required run rate to win the match is

medium

Last year, $5$ companies had an average of $16$ non working days each, and $2$ companies had $5$ fewer non working days each. What was the average number of non working days given by the same companies this $year$ ?

medium

An aeroplane travels $2500 \,km , 1200 \,km$ and $500\,km$ at $500\, km / h \,, 400 \,km $ and $250\,km / h $ respectively. The average speed is:(in $km/h$)

hard

The average of the boys in a class is $16\, years$ and that of girls is $15\, years.$ The average age for the whole class is

medium

The bowling average of a cricketer was $12.4 .$ He improves his bowling average by $0.2$ points, when he takes $5$ wickets for $26$ runs in his last match. The number of wickets taken by him before the last match Was?

easy