You would want to multiply equation a by -5 so you can eliminate by addition
2+5+8+11+14+17+20+23+26+29+32+35
Answer:
A. 3.2307692308 batches of Muffins
B. 16 1/4 cups of flour
Step-by-step explanation:
Lauren is making muffins. Her muffin recipe calls for 3 1 −4 cups of flour. She has 10 1 −2 cups of flour.
A. Explain a method for determining the number of batches of the muffin recipe Lauren can make. Then use your method to find the number of batches she can make.
Her muffin recipe calls for 3 1 −4 cups of flour. She has 10 1 −2 cups of flour.
3 1/4 cups of flour = 1 batch of Muffin recipe
10 1/2 cups of flour = x
3 1/4 × x = 10 1/2 × 1
x = 10 1/2 ÷ 3 1/4
x = 21/2 ÷ 13/4
x = 21/2 × 4/13
x = 42/13
x = 3.2307692308 batches of Muffins
B. If Lauren plans to make 5 batches of the muffin recipe, use what you know about operating with rational numbers to predict the amount of flour she needs. Justify your prediction.
3 1/4 cups of flour = 1 batch of Muffin recipe
Hence,
1 batch = 3 1/4 cups of flour
5 batches = x
Cross Multiply
x = 5 × 3 1/4 cups of flour
x = 5 × 13/4
x = 65/4
x = 16 1/4 cups of flour
In addition to mean and sample size you will need the individual scores.
The formula for standard deviation is:
S^2 = E(X-M)^2/N-1
Here's an example:
Data set: 4,4,3,1
Mean: 3
Sample size: 4
First, put the individual scores one after the other and subtract the mean from it.
4 - 3 = 1
4 - 3 = 1
3 - 3 = 0
1 - 3 = -2
Second, square the answers you got from step 1.
1^2 = 1
1^2 = 1
0^2 = 0
-2^2 = 4
Third, plug the values from step 2 into the formula.
S^2 = (1+1+0+4)/(4-1) = 6/3 = 2
Standard deviation = 2
