1. Ripple carry adder Tcarry= 4*(5+5)=40 Tsum=(4-1)*(5+5)+2*10=50 Total propagation delay=40+50=90 ns
Carry look ahead adder
TSUM = Pi+Ci
. = Exor+ and+or+exor gate time
. = 10+5+5+10=30 ns
@iarnav getting same 80 for rca