If 40% of k is 10 less than 1800% of 10, then k is:

Correct option is A

Given:

40% of k is 10 less than 1800% of 10

Solution: 

From the condition;

40% of k = (1800\% \text{ of } 10) - 10

$$0.4k = \left( \frac{1800}{100} \times 10 \right) - 10$$​​

0.4k = 180 - 10 = 170

k = $$\frac{170}{0.4}$$​ = 425