[Insert generic name here] is trying to bake a yellow cake because [reasons]. This recipe will make one whole cake.
[tex]3\frac{1}{4}\ cups\ of\ flour\\ 2\frac{1}{2}\ teaspoons\ of\ baking\ soda\\ \frac{1}{2}\ teaspoon\ of\ salt \\ 1\frac{3}{4}\ cups\ of\ sugar \\ \frac{2}{3}\ cup\ of\ butter \\ 2\ eggs\\ 1\frac{1}{2}\ teaspoons\ of\ vanilla\ \\ 1\frac{1}{4}\ cups\ of\ milk[/tex]
He wants to make three cakes instead of one. How much of each item should be used in the new (scaled-up) recipe?
[tex]3\frac{1}{4}*3=9\frac{3}{4}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ cups\ of\ flour\\ 2\frac{1}{2}*2=4\frac{2}{2}=4+1=5\ \ \ \ \ teaspoons\ of\ baking\ soda\\ \frac{1}{2}*3=\frac{3}{2}=1\frac{1}{2}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ teaspoons\ of\ salt \\ 1\frac{3}{4}*3=3\frac{9}{4}=3+2\frac{1}{4}=5\frac{1}{4}\ cups\ of\ sugar[/tex]
[tex]\frac{2}{3}*3=\frac{6}{3}=2\ \ \ \ \ \ cups\ of\ butter\\ 2*3=6 \ \ \ \ \ \ \ \ \ \ \ \ eggs\\ 1\frac{1}{2}*3 = 3\frac{3}{2} = 4\frac{1}2\ teaspoons\ of\ vanilla\ \\ 1\frac{1}{4}*3=3\frac{3}{4}\ \ \ \ \ \ \ \ cups\ of\ milk[/tex]
I don't know exactly how your teacher wants you to write out the work, but I have it pretty simple there. It's not like math is tailored to a specific process; any sort of reasonable work should do.
Good luck!
