Answer
$36.59$%.
Work Step by Step
It is the summation of the relative frequencies of "30-34", "35-39" and "40-44": $0.2257+0.1152+0.0250=36.59$%.
Or:
The relative frequency of live births were to mothers of age 29 or youger is the cumulative relative frequency of 25-29 $=0.6341$
The relative frequency of live births were to mothers of age 30 or older $=1-relative~frequency~of~live~births~were~to~mothers~of~age~29~or~youger=1-0.6341=0.3659=36.59$%.
