Order of operations
Parenthesis, Exponents/Power, Multiplication, Division/Modulus, Addition, Subtraction
Notation example
(a2 * b) + c – d
1. a2
2. * b
3. + c
4. – d
Proportions
a / A = x / X
| a | b | |
| — | = | — |
| A | B |
You’re trying to solve x. You have to cross-multiply. Be mindful of order of operations.
x * A = a * X x = a * X / A
Because I’m so nice, I coded up a very basic proportions calculator for you. Give it a try now!
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