I bought 2 pencils at 12c each and 5 pens at 24c each. I also bought 7 identical notebooks. I was told the total was $5. Why couldn't that be right?
Notebooks couldn't be the same price in a whole number of pence
A teacher has 30 pens and 45 pencils, that he wants to give to his students. If every student were to receive an equal number of pens and an equal number of pencils (with none left over), what is the maximum number of students that he could have?
Put numbers 7, 8 and 9 at the corners of a triangle. Now place 1, 2, 3, 4, 5, 6 in twos on each side to make the same total on all three sides (include the numbers at the corners)?
An Egyptian mummy is carbon-dated and compared with a scroll found in the Dead Sea, which is known to be 2000 years old. The 14C: 12C ratio of the mummy is found to be 2/3 that of the scroll. How old is the mummy?
Details and Assumptions: * 14C is radioactive with a half-life of 6000 years (it decays into nitrogen). 12C is a stable isotope, so the amount of 12C in a sample remains constant over time. * The ratio 14C:12C in an organism (plant or animal) at the time of its death is equal to the ratio of the isotopes in the air it breathed in. This ratio can be assumed to be constant over time.
I was right in the middle of February this year. I was at the end 5 years back and at the beginning 500 years ago. What am I?
The digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 can be arranged into an addition sum to add up to almost any total, except that nobody has yet found a way to add up to 1984. However 9 digits can equal 1984 by an addition sum. Which digit is omitted?
