The pie chart shows how a baby spends one day. What percentage of the day is spent sleeping, rounded to the nearest integer? Chart labels: Eating, Playing, Sleeping.
A rectangle is five times as long as it is wide. Decreasing its length by 20 cm and increasing its width by 20 cm increases its area by 1200 cm². Find its original area in cm².
Miley puts one number in each of the seven cells. The three numbers on each diameter sum to 20, and the six numbers around the circle sum to 36. What number belongs in the centre?
Fermat writes three positive numbers. For each number he adds that number to the average of the other two, obtaining 42,44,48. What is the largest original number?
For a positive integer n, f(n) is the exponent of the largest power of 2 dividing n. The source gives the example “f(40)=3 as $20=2^3\times 5$”. Find f(N) for $N=1\times 2\times\cdots\times 2023$.
Editorial note: the displayed factorisation in the example has a typographical error; use the stated definition of f.
Six cards carry 20,30,40,50,60,70. Taylor removes some cards so the product of the remaining numbers is a perfect square. What is the least number removed?
A box contains balls numbered 1 to 100. Taking and keeping a ball costs USD 0.50. A player wins upon obtaining two balls whose numbers sum to 111. What is the minimum total payment that guarantees a win?
Two identical 8 cm× 32 cm rectangles overlap as shown. Find the difference between the total white area and the shaded area. The white area means all unshaded parts of the two rectangles.
Oliver joins two identical cuboid blocks in three face-to-face ways, producing total surface areas 480 cm²,432 cm²,528 cm². Find the shortest side of one block.
Apples cost 5 dollars per bag of 4, and mangoes cost 8 dollars per box of 6. Only whole bags and boxes may be bought. A cake needs one apple and one mango. Spending exactly 88 dollars, what is the largest number of cakes possible?