Solution: (b)

The given number series question is based on the following pattern:

\(\displaystyle 8-7=1={{1}^{3}}\)

\(\displaystyle 16-8=8={{2}^{3}}\)

\(\displaystyle 43-16=27={{3}^{3}}\)

\(\displaystyle ?-43=64={{4}^{3}}\)

\(\displaystyle 232-107=125={{5}^{3}}\)

Solution: (c)

The given number series question is based on the following pattern:

\(\displaystyle 1\times 8=8\)

\(\displaystyle 8\times 9=72\)

\(\displaystyle 72\times 8=576\)

\(\displaystyle 576\times 9=5184\)

\(\displaystyle 5184\times 8=41472\)

Solution: (c)

The given number series question is based on the following pattern:

\(\displaystyle 5555-{{7}^{2}}=5506\)

\(\displaystyle 5506-{{9}^{2}}=5425\)

\(\displaystyle 5425-{{11}^{2}}=5304\)

\(\displaystyle 5304-{{13}^{2}}=5135\)

\(\displaystyle 5135-{{15}^{2}}=4910\)

\(\displaystyle 4910-{{17}^{2}}=4621\)

Hence, the number 5531 is wrong and it should be replaced by 5555.  

Solution: (d)

The given number series question is based on the following pattern:

\(\displaystyle 1\times 1+2=3\)

\(\displaystyle 3\times 2+4=10\)

\(\displaystyle 10\times 3+6=36\)

\(\displaystyle 36\times 4+8=152\)

\(\displaystyle 152\times 5+10=770\)

\(\displaystyle 770\times 6+12=4532\)        

Hence, the number 760 is wrong and it should be replaced by 770. 

Solution: (b)

The given number series is based on the following pattern :

\(\displaystyle 6\times 2-5=7\)

\(\displaystyle 7\times 2-5=9\)

\(\displaystyle 9\times 2-5=13\)

\(\displaystyle 13\times 2-5=21\)

\(\displaystyle 21\times 2-5=37\)

\(\displaystyle 37\times 2-5=69\)

Hence, the number 26 is wrong and it should replaced by 21.