Coffee MathPro Problems > Math > Number and Quantity > Number Theory > Digits
Johann was writing out a math problem when he spilled some coffee on his paper. The result was that some digits were covered up, as shown below.
♦7♦ + ♦♦9 ----- 50♦
If all but one of the hidden areas have the same digit, find all possible values for the sum of the hidden digits
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In the addition problem below, some digits are missing. They have been replaced by x and y. Find the values of x and y.
3xy2 + 3y1 = 40x3
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