Question Ese and Oke are playing a game with two tennis balls — one yellow, one blue — concealed in a bag.   They let the

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Question What weight on which side will balance the bottom scale shown?   1 kg on the left-hand side 1 kg on the right-hand s

Question Which of the numbers below can’t you get by changing some of the + to -? 2 + 4 + 6 + 8 = 20   -8 0 6 8

Question After a square is placed on the third scale, which side of the scale is heavier?   The left side The right side The

Question In New Math City (NMC), streets follow a square grid with integer coordinates, and all distances are measured in terms of

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Question Rekha connected three identical bulbs and a battery as in the picture.   How can Rekha increase the total brightness

Question Some railroad tracks are made of 20-meter-long metal rails bolted together by metal plates. The quintessential “cli

Question In circle puzzles, dashed arrows indicate addition while solid arrows indicate multiplication. Which number will replace

Question In the following two puzzles, you can change some of the addition signs to subtraction, multiplication, division, and con

Question A fair die with 20 faces has each side labeled with a number from 1 through 10, with some labels appearing multiple times