Average of 7 consecutive numbers is 20 . largest of these numbers is

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The average of $7$ consecutive numbers is $20 .$ The largest of these numbers is

A

$20$

B

$22$

C

$23$

D

$24$

Solution

Let number be $x,(x+1),(x+2), \ldots,(x+6)$

$=\frac{1}{7} \times \frac{7}{2}(x+x+6)=x+3$

$x+3=20$

$x=20-3=17$

Largest number $=x+6=17+6=23$

Standard 13

Quantitative Aptitude

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