To verify that a given n-digit positive integer is divisible by 7, we perform the "Index of 3 Test" with the number; for example, to verify that 259 is divisible by 7, following way goes the "Index of 3 Test":
259 → 2 × 3^2 + 5 × 3^1 + 9 × 3^0 = 18 + 15 + 9 = 42. (Step 1)
42 → 4 × 3^1 + 2 × 3^0 = 12 + 2 = 14. (Step 2)
14 → 1 × 3^1 + 4 × 3^0 = 3 + 4 = 7. (Step 3)
It took 3 such steps to get 7 in the end, and we’re sure that 259 is divisible by 7. How many such steps are needed to be taken so as to make sure that 11116 is divisible by 7?
A. 2
B. 3
C. 4
D. 5
E. 6
MBM
259 → 2 × 3^2 + 5 × 3^1 + 9 × 3^0 = 18 + 15 + 9 = 42. (Step 1)
42 → 4 × 3^1 + 2 × 3^0 = 12 + 2 = 14. (Step 2)
14 → 1 × 3^1 + 4 × 3^0 = 3 + 4 = 7. (Step 3)
It took 3 such steps to get 7 in the end, and we’re sure that 259 is divisible by 7. How many such steps are needed to be taken so as to make sure that 11116 is divisible by 7?
A. 2
B. 3
C. 4
D. 5
E. 6
MBM
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
