## probability consumer will be female, will buy item between

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confused
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### probability consumer will be female, will buy item between

1.: At a certain flea maket, 35% of purchases are \$10 to \$20. The probablity that a consumer will be a male is 60%. What is the probablity that a consumer will be a female and will make a purchase between \$10 and \$20?

2.: Two sacks each contain 4 candies, 2 packs of gum, and 7 cookies. One item is randomly selected from each sack. What is the probablity that both selected items will be cookies?

stapel_eliz
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1.: At a certain flea maket, 35% of purchases are \$10 to \$20. The probablity that a consumer will be a male is 60%. What is the probablity that a consumer will be a female and will make a purchase between \$10 and \$20?
I think this is one of those "grid" exercises. So set up as:
```grid:
\$10 < x < \$30?
yes     no
+-----+-----+
male |     |     | 0.6
+-----+-----+
female |     |     | 0.4
+-----+-----+
0.35   0.65```
The events would appear to be independent, so multiply to fill things in:
```grid:
\$10 < x < \$30?
yes      no
+------+------+
male | 0.21 | 0.39 | 0.6
+------+------+
female | 0.14 | 0.26 | 0.4
+------+------+
0.35   0.65```
Then read the answer-value from the grid.
2.: Two sacks each contain 4 candies, 2 packs of gum, and 7 cookies. One item is randomly selected from each sack. What is the probablity that both selected items will be cookies?
What is the probability of drawing a cookie from one sack?

Since the sacks are independent, then what is the probability of drawing cookies from both sacks?

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