Question

answer question 11 given on photo

Answer 1

hope it helps u but sorry for not doing.whole sum

Answer 2

compound interest = p(1+r/100)t
$64000(1 + {r \div 100)}^{3} = 68921 \\ (1 + r \div 100)^{3} = 68921 \div 64000 \\ 1 + r \div 100 = 41 \div 40$
R/100=(41/40) -1
r =1/40*100
=5/2= 2.5