Answer:
1.05 ± 0.05 lbs
Step-by-step explanation:
Hi!
We can calculate this interval with the z-score of the 90% which is (by convention) 1.645
The interval is calculated as follows:
[tex]x_m \pm 1.654(\frac{\sigma}{\sqrt n})[/tex]
where x_m is the mean, σ the standar deviation and n is the number of samples:
replacing these values we get:
[tex]1.05 \pm (1.645 \times \frac{0.23}{\sqrt 65})\\1.05 \pm 0.046[/tex]
*rounded to the first decimal*
1.05 ± 0.05
