Answer:
b) yes
The manufacturer has the right to state that the light bulbs last on average 400 hours
Step-by-step explanation:
<u><em>Explanation:-</em></u>
<em>Given sample size 'n' = 64</em>
<em>Given standard deviation of the Population (σ)=100</em>
<em>Mean of the sample (x⁻) = 350 hours</em>
<em>95% of confidence interval is determined by</em>

(
(350-24.5 , 350+24.5)
<em>(325.5 , 374.5)</em>
<u><em>Conclusion:-</em></u>
<u><em>Yes</em></u>
The manufacturer has the right to state that the light bulbs last on average 400 hours
Step-by-step explanation:
the 1st shop=196-(17.5/100×196)
=196-34.3
=161.7+196
=357.7
the 2nd shop=196-(22.5/100×196)
=196-44.1
=151.9+196
=347.9
so the difference between two shop is
357.7-347.9=9.8
When you subtract them you get the answer 57.99
=(1/2) * 2 * 3.2 + (1/2) *2 * 3.2 + (1/2) * 2 * 4 + (1/2) * 2 * 4
= 2 * 3.2 + 2 * 4
= 2 * (3.2 + 4)
= 2 * 7.2
= 14.4 sq feet
2 * 14.4 = 28.8 sq feet