Poppy has 30 beads.the probability of taking out a red bead is 0.4. How many red beads are there?

Question

It's so hard

 

Answer 1

Hi there, Lucy.

 

Poppy has 30 beads, and the probability of taking a red bead is 0.4. As a fraction, 0.4 would be written 2/5. What this means is that for every 5 beads Poppy has, 2 of them will be red. Let "x" represent the amount of red beads Poppy has. Everything should be written proportionately, like so:

 

x/30=2/5

 

Cross-multiply to derive:  5x=60

Divide everything by the coefficient of "x" ( in this case, the coefficient is 5 ) to derive the solution: x= 12.

 

So Poppy has 12 red beads:)!