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The Museum of Science in Boston has an exhibit in which metal balls drop down a chute, bounce around, and wind up in one of 21 bins. After 1000 balls have dropped, the heights within the bins clearly follow a bell-shaped curve. The standard deviation is 3 bins. About how many balls are in bins 1 through 17? 500 680 950 975

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shallomisaiah19

Answer:

Step-by-step explanation:

The total number of bin is 21

the mean of 21 bins is

[tex]=\frac{21}{2} \\\\=10.5\\\\\approx11[/tex]

The standard deviation is 3 bins.

We calculate , by using z formula

[tex]P(x<7)=P(z<\frac{x-\mu}{\sigma} \\\\=P(z<\frac{7-11}{3} )\\\\=P(z<-1.33)\\\\=0.0918 (z \ \ table)\\\\\therefore P(x<7)=0.0918[/tex]

Since after 1000 balls is drop, we will mutiply with 1000

0.0918  x 1000

= 91.8

≅ 92

Therefore, we have 92 balls