Fun math problem
May 11th, 2019 at 11:40:36 AM
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I stumbled across this fun math problem the other day and it took me longer than it should have to figure out the solution. I am sure the mathletes on here will have no problem with it. 2+3=28; 4+5=54; 6+7=80; 1+4=19; 8+8=104; 1+9=?
May 11th, 2019 at 3:12:11 PM
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Thanks - it was fun working it out.
The pattern to recognise is that it's (10 x the first number) plus something
The something is the first number plus twice the second number. This method is easier to work out than 11a+2b.
May 11th, 2019 at 6:08:07 PM
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Charlie,not sure how to post spoilers on here,so I sent you a PM with my solution. Did not want to show my solution in case someone else want to try their hand at this.
May 12th, 2019 at 2:19:32 AM
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Thanks - yes I agree (sent PM back). If you look below the box where you enter text then you can see the "click here for formatting codes" ( https://wizardofvegas.com/forum/info/help/1-formatting-codes/ ) and see (open brackets)spoiler(close brackets) text (open brackets)/spoiler(close brackets). Another way is to quote this reply and see how the following spoiler works.
You can also use preview to see whether your spoiler actually works before posting a reply (warning if your close /SPOILER etc are missing this can go wrong so if it goes awry check your opening and closing tags).
1x11 + 2x9 = 11+18 = 29
May 12th, 2019 at 3:16:13 AM
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x + y = xy + (x+y)
1 + 9 = 19 + (1+9) = 29
1 + 9 = 19 + (1+9) = 29
“You don’t bring a bone saw to a negotiation.” - Robert Jordan, former U.S. ambassador to Saudi Arabia
May 12th, 2019 at 9:32:58 AM
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That was the solution I came up with also. I did a face Palm when I finally figured it out. Thanks for replying BCS
May 12th, 2019 at 11:00:25 AM
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Thanks for posting the puzzle.
I suspect a large part of the difficulty you had was caused by the way the problem is given. That is, as mathematical statements with mathematical operators. That is probably an intentional effort to make solving the riddle harder. Had the problem been stated this way you might have had an easier time solving it:
2,3->28 4,5->54 6,7->80 1,4->19 8,8->104 1,9->?
“You don’t bring a bone saw to a negotiation.” - Robert Jordan, former U.S. ambassador to Saudi Arabia
May 12th, 2019 at 6:26:24 PM
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You are very welcome. And you are correct in your assumption
