The surface area of sphere = 4πr^{2 }
4πr^{2} = 616
r^{2} = 616 × 7/4 × 22 = 49
r = √49
r = 7 cm
Vol. of big sphere = 4/3πr^{3} = 4/3 × 22/7 × (7)^{3}
Vol. of small sphere = 4/3π(3.5/2)^{3}
∴ No. of smaller sphere = Vol. of big sphere/Vol. of small sphere
= (4/3π(7)^{3})/(4/3π(3.5/2)^{3})
= 64