BTGmoderatorLU wrote:Source: Princeton Review
At the local grocery store, apples normally cost 40 cents each. During a recent sale, the price was reduced to 3 apples for a dollar. How much money would be saved by purchasing 30 apples at the sale price?
A. $1
B. $1.50
C. $2
D. $2.50
E. $3
Trivial application of UNITS CONTROL, one of the most powerful tools of our method!
$$?\,\,\,\left[ \$ \right]\,\,\, = \,\,\,30\,\,{\rm{apples}}\,\,\,\left( {{{\,40\,\,{\rm{cents}}\,} \over {1\,\,{\rm{apple}}}}} \right)\,\,\,\left( {{{1\,\,{\rm{\$ }}} \over {\,100\,\,{\rm{cents}}\,}}} \right)\,\,\,\, - \,\,\,30\,\,{\rm{apples}}\,\,\left( {{{1\,\,{\rm{\$ }}} \over {\,3\,\,{\rm{apples}}\,}}} \right)\,\,\,\,\, = \,\,\,3 \cdot 4 - 10\,\,\, = \,\,\,2\,\,\,\,\,\left[ \$ \right]$$
This solution follows the notations and rationale taught in the GMATH method.
Regards,
Fabio.