Answer:
(8.213 ; 8.247)
Step-by-step explanation:
Given the data :
No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Dia. 8.23 8.16 8.23 8.25 8.26 8.23 8.20 8.26 8.19 8.23 8.20 8.28 8.24 8.25 8.24
Sanple size, n = 15
Sample mean, xbar = Σx / n = 123.45 / 15 = 8.23
The sample standard deviation, s = √(x -xbar)²/n-1
Using calculator :
Sample standard deviation, s = 0.03116
s = 0.031 (3 decimal places)
The 95% confidence interval :
C.I = xbar ± (Tcritical * s/√n)
Tcritical at 95%, df = 15 - 1 = 14
Tcritical = 2.145
C.I = 8.23 ± (2.145 * 0.031/√15)
C.I = 8.23 ± 0.0171689
C.I = (8.213 ; 8.247)
Answer:
1) 3 beads
2) 12 beads
3) (4x3)+3=15
Step-by-step explanation:
Is it OK if I explain it before I write down the next term ?
-1 ___ 3 ___ 11 ___ 23 ___ 39 ___ ( )
The first blank is . . . . . " + 4 = " .
The second blank is . . " + 8 = " .
The third blank is . . . . " + 12 = " .
The fourth blank is . . . " + 16 = " .
So the fifth blank is . . . " + 20 = " and the next number is 59 .