Forget the conventional way to solve DS questions.
We will solve this DS question using the variable approach.DS question with 1 variable: Let the original condition in a DS question contain 1 variable. Now, 1 variable would generally require 1 equation to give us the value of the variables.
We know that each condition would usually give us an equation, and since we need 1 equation to match the number of variables and equations in the original condition, the equal number of equations and variables should logically lead to answer D.
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Let’s apply the 3 steps suggested previously. [Watch lessons on our website to master these 3 steps]
Step 1 of the Variable Approach: Modifying and rechecking the original condition and the question.We have to find whether the units digit of N equal to zero.
Second and the third step of Variable Approach: From the original condition, we have 1 variable (N). To match the number of variables with the number of equations, we need 1 equation. Since conditions (1) and (2) will provide 1 equation each, D would most likely be the answer.Let’s take a look at each condition.Condition(1) tells us that 14 and 35 are factors of N.=> 14 = 2 * 7 and 35 = 5 * 7.
=>This means 'N' is divisible by 10 and it must have a unit digit equal to '0'
Since the answer is unique, the condition is sufficient by CMT 2.Condition(2) tells us that N = \((2^5)(3^2)(5^7)(7^6)\)=> Combiantion of 2 * 5 = 10 ensures that 'N' has unit digit as '0'
Since the answer is unique, the condition is sufficient by CMT 2.Both conditions (1) and (2) alone are sufficient.So, D is the correct answer.Answer: D _________________