Solve This : 4 x 7 = ?

Answer of the puzzle (Solve This : 4 x 7 = ?) is : 20

How : Its the product between number of word in the digit

Five x Four = ( Number of letter in FIVE) x (Number of letters in Four) = 4 x 4 = 16

so

4 x 7 = ( Number of letter in FOUR) x ( Number of letter in SEVEN) = 4 x 5 = 20