The ratio of boys to girls in a class is 2:3. If there are 18 girls in the class, what is the probability of a boy being in the class, P(boy)? SHOW WORK to verify your choice.

Respuesta :

frika

Answer:

0.4

Step-by-step explanation:

If the ratio of boys to girls in a class is 2:3, then

  • there are 2x boys;
  • there are 3x girls.

If there are 18 girls in the class, then

[tex]3x=18\\ \\x=6[/tex]

Thus, there are

  • [tex]2\cdot 6=12[/tex] boys;
  • [tex]3\cdot 6=18[/tex] girls;
  • [tex]12+18=30[/tex] students in total.

The probability of a boy being in the class is

[tex]P=\dfrac{12}{30}=\dfrac{2}{5}=0.4[/tex]