Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 9 Answered

the mean of 25 observations is 36.Out of these observations, the mean of first 13  observations is 32 and that of last 13 observations is 40, find the 13th observation ?
Asked by nisha_vini29 | 25 Jan, 2016, 11:22: AM
answered-by-expert Expert Answer

begin mathsize 14px style M e a n space o f space 25 space o b s e r v a t i o n s equals 36 rightwards double arrow S u m space o f space 25 space o b s e r v a t i o n s equals 25 cross times 36 equals 900 M e a n space o f space f i r s t space 13 space o b s e r v a t i o n s equals 32 rightwards double arrow S u m space o f space f i r s t space 13 space o b s e r v a t i o n s equals 13 cross times 32 equals 416 M e a n space o f space l a s t space 13 space o b s e r v a t i o n s equals 40 rightwards double arrow S u m space o f space l a s t space 13 space o b s e r v a t i o n s equals 13 cross times 40 equals 520 N o w comma space 13 t h space o b s e r v a t i o n equals s u m space o f space f i r s t space 13 space o b s e r v a t i o n s plus S u m space o f space l a s t space 13 space o b s e r v a t i o n s space minus S u m space o f space 25 space o b s e r v a t i o n s equals 416 plus 520 minus 900 equals 36 end style

Answered by | 25 Jan, 2016, 06:02: PM

Application Videos

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 9 - Maths
laxman saves 10% More than his expenditure and bhuwan spends 10% more than his savings if laxman savings is 10% more than bhuwan expenditure what is the ratio of incomes of laxman and bhuwa
Asked by rathorgaurav2945 | 21 Apr, 2024, 10:31: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
13. If x = (2 + sqrt(3)) find the value of x ^ 2 + 1/(x ^ 2)
Asked by monika.vns14 | 18 Apr, 2024, 05:15: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
3√5+√3/√5-√3
Asked by gulshanelectronics2017 | 15 Apr, 2024, 05:35: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
find the value of n in 7^2n+1÷49=7^3
Asked by tripura78839 | 12 Apr, 2024, 09:05: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
how to solve it
question image
Asked by singhanjali0199 | 12 Apr, 2024, 08:29: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
√2x^2+3x+√2
question image
Asked by killerstealer593 | 11 Apr, 2024, 07:50: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
x²-22x+120
Asked by rson0295 | 01 Apr, 2024, 08:55: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
Draw the graph of the equation of line 2x + 3y = 6. Write the co ordinates of the point where the line intersects X-axis and Y-axis.
question image
Asked by saee.shinde3069 | 31 Mar, 2024, 10:12: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
locate √2 on number line
Asked by rathoreraj7296 | 31 Mar, 2024, 08:09: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 9 - Maths
ab is diameter of circle with centre o . CD is a code equal to the radius of the circle a c and b b when extend intersect at the point e prove that angle a e b is equals to 60 degree
Asked by divyanshibirla037 | 29 Mar, 2024, 03:26: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×