There are 7 students in a class: 5 boys and 2 girls. If the teacher picks a group of 4 at random, what is the probability that everyone in the group is a boy?

4/7

Step-by-step explanation:

5+2=7

7 children

4 boys Out of 7 children

1/7

Step-by-step explanation:

Khan academy

step-by-step explanation: you take each of the numbers and divide by the amount then you take the range

30 miles

step-by-step explanation:

we know that 60 seconds equals 1 minute and 60 minutes 1 hour

44 ft       60 sec     60 min     158400   ft

  *   *   =

1 sec       1 min       1 hour         hour

we know that there are 5280 ft per mile

158400   ft       1 mile         30 miles

  *   =

1   hour               5280 ft     1 hour

so in 1 hour   it can travel 30 miles