The mean weight of $9$ items is $15$ . If one more item is added to the series the mean becomes $16$ . The value of the $10^{t h}$ item is

35

No worries! We‘ve got your back. Try BYJU‘S free classes today!

30

No worries! We‘ve got your back. Try BYJU‘S free classes today!

25

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

20

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C $25$
Assuming original nine elements are $x_{1}, x_{2}, x_{3}, . . . . . . . . . x_{9}$ and new element is $x$
Sum of original nine elements is $9 \sum i = 1 x_{i} = 9 \times 15 = 135$
Given new mean after addition of $x$ is 16. $\Rightarrow \frac{9 \sum i = 1 x_{i} + x}{10} = 16$
$\Rightarrow \frac{135 + x}{10} = 16 \Rightarrow x = 160 - 135 = 25$

Suggest Corrections

Similar questions

Size of item	$10 - 15$	$15 - 20$	$20 - 25$	$25 - 30$	$30 - 35$	$35 - 40$	$40 - 45$	$45 - 50$
No. of items	$4$	$8$	$18$	$30$	$20$	$10$	$5$	$2$

40

50

64

42

Items	0−5	5−10	10−15	15−20	20−25	25−30	30−35	35−40
Frequency	2	5	7	13	21	16	8	3

10

6

4

7.5

Join BYJU'S Learning Program