If someone can help I would appreciate it

Hannah is 3 years older than twice her brother joey’s age. joey is 2 years old. how old is hannah? show all of your work! the number of students is five more than seven times the number of teachers. there are 10 teachers. how many students are there? be sure to show all of your work!

Afactory adds 3 red drops and 2 blue drops of coloring to white paint to make each pint of purple paint. the factory will make 50 gallons of the purple paint.how many drops of red and blue coloring will the factory need in the 50 gallon batch of purple paint.

How is working backward similar to solving an equation?