T Tryingtodowell Active Member Joined Jan 18, 2024 Messages 216 Gender Female HSC N/A Apr 26, 2024 #1 I JUST DONT GET THIS TOPIC hardest ext 1 topic for me
WeiWeiMan Well-Known Member Joined Aug 7, 2023 Messages 915 Location behind you Gender Male HSC 2026 Apr 26, 2024 #2 Tryingtodowell said: View attachment 42984 I JUST DONT GET THIS TOPIC hardest ext 1 topic for me Click to expand... a. 9 choices for first digit (can't be 0), 9,8,7 etc for next digits total = 9*9*8*7*6*5*4*3*2*1=9*9! = 3265920 b. 9 choices for first digit (can't be 0), 10 for each subsequent digit total = 9 * 10^9 [9 other digits]
Tryingtodowell said: View attachment 42984 I JUST DONT GET THIS TOPIC hardest ext 1 topic for me Click to expand... a. 9 choices for first digit (can't be 0), 9,8,7 etc for next digits total = 9*9*8*7*6*5*4*3*2*1=9*9! = 3265920 b. 9 choices for first digit (can't be 0), 10 for each subsequent digit total = 9 * 10^9 [9 other digits]