This fifth-grade math problem leaves adults on the internet questioning their own IQ

Puzzles and math problems are a fun way to stretch your brain. But every now and then, one comes along that really stumps you. That’s exactly what happened when Reddit user u/springwaterh20 posted a math problem that left people scratching their heads. Despite being posted two years ago, it’s still leaving people puzzled. The problem came from a 5th-grade test and was captioned, "A test problem on my 5th grade brother's math exam." Most adults might assume they could easily solve a fifth-grade math problem—until they actually see this one.

According to Indy100, the now-deleted post said, "Klein read 30 pages of a book on Monday and 1/8 of the book on Tuesday. He completed the remaining 1/4 of the book on Wednesday. How many pages are there in the book?" per Indy100. It left people baffled, with many offering funny responses. One user, u/SuperDuperDylan, joked, "I always think to myself: 'Ugh. People should really be tested with basic skills before they're allowed to go out into society.' And then I see this and realize I shouldn't go out into society. Lol."

u/sneakyspider wrote, "I've read every explanation in this thread, yet I still feel clueless. Now I understand why I failed most of my math classes in high school, lol." u/intashu shared, "My kiddo is in 6th grade and often I have to double check my work or think on the question twice to help him with homework. It's just odd fractions, multiplication and division of mixed numbers, and abstract thinking I haven't done as an adult ever. Sometimes, he figures it out, then has to tell me I'm wrong too." 

u/twitterban said, "25 and still wouldn't be able to answer that question if my life depended on it." However, some people were confused because of how the math problem was phrased. u/nullrod17 shared, "My only issue is that the problem doesn't state that he started the book on Monday or that those 30 pages were the first thirty pages. Could be clarified better." u/zenfiti commented, "The problem does not state that Klein started the book on Monday. Without this information, the problem cannot be solved." Despite many people not knowing how to solve this problem, some were able to answer this question. u/lionheart2243 wrote, "How I did this in my head: After reading 30 pages, he had 3/8 of the book remaining. So 30 is 5/8 of the book. 30/5 is 6, so every 8th of the book is 6 pages. 6 x 8 = 48 pages in the book."

Another math problem left people baffled online. The equation was posted on Instagram threads by @deepak_thakur_9897 and it warned that it was only for geniuses. The equation read, "3x3-3÷3+3." Many people followed the PEDMAS rule and concluded that the answer would be 11. @harish_1811 commented, "To evaluate this expression, we need to follow the order of operations (PEMDAS): Step1- Multiply 3 and 3: 3×3 = 9. Step 2- Divide 3 by 3: 3÷3 = 1. Step 3- Subtract 1 from 9: 9 - 1 = 8. Step 4- Add 3 to 8: 8 + 3 = 11. So the final answer is 11." @mrwurst wrote, "Wait, what? When I was attending school, this was the basics of math and now it is for geniuses? And the answer is 11." However, others threw in the towel and agreed they dared not mess with the equation. @eloodie.2412 said, "My AI snap said 5."

This article originally appeared on 9.20.24.