A person can make 100 using the digit 9 four times in an equation. The equation for this math problem is: 99 + (9 / 9) = 100. This solution works because 9 divided by 9 equals 1, and 99 plus 1 equals 100.
Continue ReadingSolving this math problem requires one to notice that the number 99, which contains the digit 9 repeated twice, is very close to 100. In fact, 100 - 99 = 1. The other two 9 digits must therefore equal one, and this requires a fraction. The fraction 9 over 9 equals 1. Combining these two facts in a single equation solves this math problem, with the answer being 99 + (9 / 9) = 100.
Learn more about NumbersAn extremely difficult math equation is the Jacobi-Madden equation, a^{4} + b^{4} + c^{4} + d^{4} = (a + b + c + d)^{4} where variables a, b, c and d can be any positive integer, negative integer or zero. The Jacobi-Madden equation is considered a Diophantine equation.
Full Answer >A mathematical concept is a general idea behind an equation, problem or formula in math. In contrast to a math fact, which must be committed to memory, a math concept explains why math works in a certain way.
Full Answer >Mathematical equations called functions use input and output replace the variables in an equation. The input is the known variable, while the output is the solution. Use functions any time a variable (x) transforms in a relationship to equal a new variable (y).
Full Answer >A negative minus a negative is equal to another negative number, a positive number or zero, depending upon the numbers in the equation. Subtracting a negative number from another negative number is the same thing as adding a positive number.
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