Note :- If sample size n > 30 OR Population standard deviation σ is given then We use Z test.
If sample size n < 30 AND Population standard deviation σ is unknown then we use t test.
In this question we are not given Population standard deviations σ1 and σ2.
Also n1 = 14 and n2 = 13 both sample sizes are LESS than 30.
Therefore we use t test.
Given :- Assume the population standard deviations are equal. ( σ1 = σ2)
then Degrees of freedom = n1 + n2 - 2 = 14 + 13 - 2 = 25.
(kindly find the image attached with this solution)
Answer :- Therefore 25 degrees of freedom are used to find the t critical value.
Answer:
85 ft^2
Step-by-step explanation:
The four sides of the pyramid: 5×6÷2×4=60
The bottom of the pyramid: 5×5=25
60+25=85 ft^2
Like XZ divides the cord YV into two congruent parts (YW=5.27 cm=WV), this segment XZ must be perpendicular to the segment YV, then the angle XWY in triangle XWY is a right angle (90°) and the triangle XWY is a right angle.
We can apply the trigonometric ratios in triangle XWY:
Hypotenure: XY
sin 44°=(Opposite leg to 44°)/(hypothenuse)
sin 44°=YW/XY
sin 44°=(5.27 cm)/XY
Solving for XY. Cross multiplication:
sin44° XY=5.27 cm
Dividing both sides of the equation by sin 44°:
sin 44° XY / sin 44° = (5.27 cm)/sin 44°
XY=(5.27/sin 44°) cm
XY=(5.27/0.694658370) cm
XY=7.586462929 cm
This value XY is the radius of the circle, then:
XZ=XY→XZ=7.586462969 cm
tan 44°=(Opposite leg to 44°) / (Adjacent leg to 44°)
tan 44°=YW/XW
tan 44°=(5.27 cm)/XW
Solving for XW. Cross multiplication:
tan 44° XW=5.27 cm
Dividing both sides of the equation by tan 44°:
tan 44° XW / tan 44°=(5.27 cm)/tan 44°
XW=(5.27/tan 44°) cm
XW=(5.27/0.965688775) cm
XW=5.457244753 cm
WZ=XZ-XW
WZ=7.586462969 cm-5.457244753 cm
WZ=2.129218216 cm
Rounded to 2 decimal places:
WZ=2.13 cm
Answer: The <span>measurement is closest to the measure of segment WZ is
2.13 cm</span>
