Jennifer bought a box of Crunchy Grain cereal. The nutrition facts on the box state that a serving size of the cereal  is cup and provides 210 calories, 50 of which are calories from fat. In addition, each serving of the cereal provides 180 milligrams of potassium, which is 5% of the daily allowance for adults.
On Tuesday, Jennifer will mix Crunchy Grain cereal with Super Grain cereal for her breakfast. Super Grain cereal provides 240 calories per cup. If the total number of calories in one cup of Jennifer’s mixture is 270, how much Super Grain cereal is in one cup of the mixture?

The correct answer is:  cup

○        The concept used in this question is of representing a situation in the form of an equation.
○        In equation, LHS = RHS, always.
○        In this question, an equation with two variable is used, which contains only two variable.
○        Take constant value as it is the question and,
○        Represent variable value as x or any alphabet.

• Step by step explanation:

○        Given:
Total calories in one cup is 270 calories.
 cup of crunchy grain cereals provide 210 calories.
1 cup of crunchy grain cereals provide 280 calories.
1 cup of sugar grain cereals provide 240 calories.
○        Step 1.
Let assume jenniffer mixes x cups of crunchy grain cereals with y cups of sugar grain cereals.
So, Total calories will be,
280x + 240y = 270
And
x + y = 1
So, x = 1-y
○        Step 1.
Put x = 1 - y, in 280x + 240y = 270
280x + 240y = 270
280(1- y) + 240y = 270
280- 280y + 240y = 270
- 40y = 270 - 280
y =   
y =  
∴    cup Super Grain cereal is in one cup of the mixture

• Final Answer:

Correct option is,
Option B.  cup.