Bag with 3 red marbles, 7 white marbles, and 5 blue marbles. You draw 3 marbles replacing one before drawing the next. What is the probability a red, blue and then white marble.

7/225

Step-by-step explanation:

There are 15 marbles in the bag. The probability of drawing a red marble is 3/15 = 1/5.  If you replace that marble, then the probability of drawing a blue marble is 5/15 = 1/3 and if you replace that marble, then the probability of drawing a white marble is 7/15.  Therefore, the probability of drawing a red, blue and white marble with replacement is (1/5)(1/3)(7/15) = 7/225

she will sew have sewn five dresses   and be 1/3 done with the sixth one in an hour.

step-by-step explanation:

3/4 of an hour=45 mins

lucy makes 1 dress per 11.25 minutes

45 mins+11.25 mins=56.25 mins

60 mins- 56.25 mins=3.75 mins

3.75 mins is 1/3 of of 11.25 mins

therefore she the other 1/3 would be part of the hour and she will have sewn 5 dresses and begun the sixth.

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