Answer:
Step-by-step explanation:
Let's put the data as below:
n1=15    x1=2.8      s1=1.6       and s1²=2.56
n2=19   x2=2.4     s2=1.7        and s2²=2.89
alpha= 0.05
To test the hypothesis: 
H0= There is no sufficient evidence that low income household have fewer children
H1=There is sufficient evidence that low income household have fewer children
 Assume that population variances are equal.
the t-static for two samples,
 ~t with min (n1-1,n2-1)df
 ~t with min (n1-1,n2-1)df
The pooled variance estimate Sp equals:

Sp²=2.7456
Sp=1.65699
Degrees of freedom=n1+n2-2=32
Under null hypothesis:


The critical value ttab=2.0369 for alpha=0.05
So we reject our null hypothesis H0
So there is sufficient evidence that low income households have fewer children than high income households