What is the range of a set consisting of the first 100 multiples of 7 that are greater than 70?
Answer Choices
Correct answer marked belowSee the full step-by-step explanation
You can see the correct answer above. Sign in for free to unlock the complete worked solution.
Track your performance and improve
Get detailed analytics, unlock full explanations, and move up difficulty tiers as you practice.
Unlock the full explanation
Create a free account to reveal the correct answer, see the step-by-step explanation, and start tracking your GMAT progress.
Wait, 'first 100 multiples of 7 that are greater than 70' — does that include 70 itself? Because 70 is a multiple of 7, but it says greater than 70, so we start at 77, right? That was my main confusion.
Yes, strictly greater means 77 is the first one. If it said 'at least 70' it'd be different.
Got 707. Took me a second to realize the range is just last minus first, not something fancy. The 'first 100' wording made me overthink it for a bit.
Same here, I was about to try some AP formula for the range before realizing it's just the endpoints.
These sequence questions are always a trap for me. I keep wanting to count from 7 instead of from 77. Need to slow down and read the 'greater than 70' part carefully.
Nice one. Solid 600-level question — not hard, but punishes sloppy reading. 77 + 99*7 should give the last term, then subtract 77.
Exactly, the 99 instead of 100 trips people up if they forget the first term is already counted.
What it tests
Your ability to spot and extend arithmetic and geometric sequences and work with recursive definitions.
Common trap
Off-by-one errors in indexing (a₀ vs a₁) or confusing an arithmetic difference with a geometric ratio.