Question

A lunch cheque is \[\$27.95\] . How do you estimate a \[15\%\] tip ?

Answer 1

Hint: Problems like these are very easy to solve once we understand the underlying concepts behind the given problem. Solving problems of these kinds require a complete understanding of the topic percentage and its various applications. The word percent word is coined from the two words, “per” and “cent”. Here “cent” means, hundred and “per means” out of. So percentage is defined as something which we express in terms of hundred. So, when we write \[15\%\] , it means we want to say that for every hundredth, we want \[15\] units. In the given problem we are required to calculate the value \[15\%\] of the total cheque.

Complete step-by-step solution:
Now we start off with the solution of the given problem by writing it as, we want to find the value \[15\%\] of the total amount of the money, or in other words, we need to find \[15\%\] of \[\$27.95\] . We need to keep in mind the unitary method, to solve this problem more smoothly. \[15\%\] means \[15\] out of every hundred. Thus for \[\$1\] , this value will result to,
\[\dfrac{15}{100}\]
Now we can easily find the value for \[\$27.95\] . Applying unitary method for the problem we get,
\[\begin{align} & \text{For }\$1 \rightarrow \dfrac{15}{100}\$\\&\Rightarrow\text{For }\$27.95 \rightarrow \dfrac{15}{100}\times\$27.95\\\end{align}\]
Now, performing the required multiplication on the right hand side of the equation to find the value of the required tip we get,
\[\Rightarrow \text{For }\$27.95 \rightarrow \$4.1925\]
Thus, the total tip for the lunch is \[\$4.1925\].

Note: These types of problems require a complete understanding of the topics, percentage and unitary method. We must be very careful while doing the unitary method as it may lead to mistakes when we are multiplying the different variables. For solving these types of problems quickly we can simply write that \[x\%\] of \[y\] is equal to \[\dfrac{xy}{100}\] . Using this relation we will be able to find the answer in no time.