Find the value of 7 x 0.7 x 0.07 x 0.007 × 70 :

Correct option is D

Solution:

​$$7 \times 0.7 \times 0.07 \times 0.007 \times 70 \\\ \\= 7 \times \frac{7}{10} \times \frac{7}{100} \times \frac{7}{1000} \times 70\\\ \\= 7 \times 7 \times 7 \times \frac{1}{100} \times \frac{7}{1000} \times 7\\\ \\= \frac{16807}{10000} = 0.16807$$​​