Ajit has a certain average for 9 innings. In the tenth innings, he scores 100 runs thereby increasing his average by 8 runs. His new average is:
A. 20
B. 21
C. 28
D. 32
Answer: Option C
Solution (By Examveda Team)
Let Ajit's average be x for 9 innings. So, Ajit scored 9x run in 9 innings.In the 10th inning, he scored 100 runs then average became (x+8). And he scored (x + 8) × 10 runs in 10 innings.
Now,
$$\eqalign{ & \Rightarrow 9x + 100 = 10 \times \left( {x + 8} \right) \cr & {\text{or}},\,9x + 100 = 10x + 80 \cr & {\text{or}},\,x = 100 - 80 \cr & {\text{or}},\,x = 20 \cr & {\text{New}}\,{\text{average}} = \left( {x + 8} \right) \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, = 28\,{\text{runs}} \cr} $$
This Question Belongs to Arithmetic Ability >> Average
Can i get shortcut method of it
Correct Answer 28
Please explain in short cut method
please explain in short cut methods.
Thanks
Where can I get the theory of this chapter
9x8 =72
100-72 = 28 ans new avg
Alright
Alright
Thanks
Nice explaination
Right
Is it right
How it becomes (x+8)
Very helpful
Average= Total or Sum / Number (Total divided by Number)
For 9th inning
x = T/9
9x=T
For 10th inning
x+8=T/10
10(x+8)=T
9x+100=10(x+8)
9x+100=10x+80
x=20
New Average:x+8=28
_____________________________________
Shortcut:
Innings×increasing runs=Answer
Then, Runs-Answer=New Average
9×8=72
Then, 100-72=28
New Average:28
10x8 = 80
100-80 =20
New increment = 20+8
Let's do it in shortcut
Assume Till 9th inng his avg will be x
In 10th inng his score was 100 and his total avg increase by x+8
I.e for previous 9 innengs 8 will be given to each inngs
So 9*8 = 72 and for 10th inng it's already 100 so
100-72=28
Nice
Thanks
Awesome app mainly board writing idea 🙂👍
Nice sir
(9*8)= 72
100-72=28
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Salimreza Jim :
100-(8*9)=28
Nice Sir
how can this possible?
Well awsm app for good method has been
Ok, Good.., But when student doing competitive exams we they short cut method, plz explain in short cut methods
It's the so best learning website to improve mathematical calculation
100-(8*9)=28
Good
Let, initial average = x
Acq,
10(x+8)-9x = 100
x = 100-80 = 20
New average = 20+8 = 28
thanks
thanks
Good and clear explanation
Good Solutions
Didn't get it.
Let Ajit's average be x for 9 innings. So, Ajit scored 9x run in 9 innings.
In the 10th inning, he scored 100 runs then average became (x+8). And he scored (x+8)*10 runs in 10 innings.
(9x+100)/10 = x+8 (since in 10th inning, 100 more then 9th inning and average gets increses by 8)
therefore on solving this equation we get ,
x=20
But the new average is increased by 8 runs
therefore x+8 i.e 20+8 = 28..
Nice solution
Can't understand
c
28
Best questions
c
Its 28
28