Maths Olympiad Prep

Track / Stage 2 / 63 of 320 #383 of 2604

Problem 383

Number theory Difficulty 2.0 Find the answer UKMT Intermediate Mathematical Challenge · United Kingdom · 2020

The result of the calculation 9×11×13×15×179 \times 11 \times 13 \times 15 \times 17 is the six-digit number '3n81853n8185'. What is the value of nn? (A) 22 (B) 44 (C) 66 (D) 88 (E) 00

The source for this one didn't record the answer, so there is nothing to check what you type against. Work it on paper and mark yourself against the solution below.

Next problem →

We don't reproduce this publisher's solutions. Their own solution is here — work the problem first.

Source: UK Mathematics Trust, licensed © UK Mathematics Trust; past papers published free at ukmt.org.uk. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project. Solutions are the publisher's, linked not copied.