Answer:

Step-by-step explanation:
Given
Age 11 Age 12 Total
Girls 3 5 8
Boys 1 3 4
Required

The number of aged 12 children is:


The total number of children is:

So, we have:


Simplify

Answer:
1.2 km/min
Step-by-step explanation:
ROC? rate of change? if not rate of change than my answer may not be correct
24km/20min = 1.2 km/min
24km/20min * 60min/1 hr= (24*60)/20=120 km/hr
9-4=5
unless I am reading the question wrong I believe the answer is nine.