Evaluating expressions with variables word problems

Evaluating expressions with variables word problems
Description
Exercise Name:	Evaluating expressions with variables word problems
Math Missions:	6th grade (U.S.) Math Mission, 7th grade (U.S.) Math Mission, 8th grade (U.S.) Math Mission, Algebra basics Math Mission, High school geometry Math Mission, Mathematics I Math Mission, Algebra I Math Mission, Mathematics II Math Mission, Algebra II Math Mission, Mathematics III Math Mission
Types of Problems:	2

The Evaluating expressions with variables word problems exercise appears under the 6th grade (U.S.) Math Mission, 7th grade (U.S.) Math Mission, 8th grade (U.S.) Math Mission, Algebra basics Math Mission, High school geometry Math Mission, Mathematics I Math Mission, Algebra I Math Mission, Mathematics II Math Mission, Algebra II Math Mission and Mathematics III Math Mission. This exercise uses word problems to practice evaluation of functions and formulas.

Types of problems

1. Word Problems - There are word problems in this exercise which help in understanding how evaluating expressions with variables can be used in real life. Users are expected to solve the question from the word problem.

Solve the word problem

Strategies

It's hard to get both accuracy badges and speed badges in this exercise.

1. Substituting the value of the unknowns into the expression may take some time and finding the value of the expression will take a lot of time. In the problems shown in the right, it may take time to raise ${\frac{2}{3}^4}$ as ${n}$ in $\frac{2}{3}$.

Real-life Applications

1. Knowledge of algebra is essential for higher math levels like trigonometry and calculus. Algebra also has countless applications in the real world.
2. Work problems often ask us to calculate how long it will take different people working at different speeds to finish a task. The algebraic models of such situations often involve rational equations derived from the work formula, ${W = rt}$. The amount of work done (${W}$) is the product of the rate of work (${r}$) and the time spent working (${t}$). The work formula has 3 versions:
   ${W = rt}$
   ${t = \frac{W}{r}}$
   ${r = \frac{W}{t}}$