Question

How do you translate “18 more than a number” into a mathematical expression?

Answer 1

Hint: We know that mathematical expression and algebraic expression are both the same. An algebraic expression in mathematics is an expression which is made up of variables and constants along with algebraic operations. An expression is a group of terms. Here algebraic operations are addition, subtraction, division and multiplication etc. We know that if we have ‘more than’ we need to add the operation addition. If we have ‘times’ we need to put operation multiplication.

Complete step-by-step solution:
We have “18 more than a number”.
Let the unknown number be ‘n’. Which is unknown.
Thus we have,
\[ \Rightarrow 18 + n\] is the required algebraic expression.
Because we have a constant ‘18’ and a variable ‘n’. Also we have algebraic operations addition and multiplication.
(A variable is a symbol for a number that we don’t know yet. Generally it is represented by alphabetic letters. A number on its own is called a constant)

Hence the final answer is \[ 18 + n\]

Note: Suppose let's say we need to convert “18 less than a number” into an algebraic expression. We know if we have ‘less than’ we need to put negative operation. Then we have the algebraic expression \[ \Rightarrow 18 - n\]. Let’s see some algebraic expression which are translated form words:
i) ‘a’ times ‘b’\[ \Rightarrow a \times b\]
ii) ‘a’ divided by ‘b’\[ \Rightarrow \dfrac{a}{b}\].