Total number of yards of ribbon available = 25 yards.
Number of yards of fabric available = 30 yards.
Number of yards of ribbon a child need = 1.75 yards
Number of yards of fabric a child need = 2.8 yards.
<em>Total number of children participate in the activity for 25 yards of ribbon = 25/1.75 = 14.28 approximately 15 children.</em>
<em>Total number of children participate in the activity for 30 yards of fabric = 30/2.8 = 10.7 approximately 11 children.</em>
<h3>Therefore, maximum 11 children can participate in the activity because each child required both 1.75 yards of ribbon and 2.8 yards of fabric .</h3>