Replace a with 4 and b with -12
3(4) + -12/4 + 4(4) = 16+-12/4+4*4 = 29
Answer:
90
Step-by-step explanation:
well These are the Images on how to add decimals.
We can use a rule of three simple, direct proportion to solve this problem.
15 pounds correspond to $1.80, then the question is to find the price of one pound, the called unit rate. We state the rule of three:
15 pound ----> $1.80
1 pound -----> x
x = (1)(1.80)/15
x = 0.12
Therefore, each pound costs $0.12 that is the unit rate in pounds
Below are the choices:
A. 80 mL of the 3.5% solution and 120 mL of the 6% solution
<span>B. 120 mL of the 3.5% solution and 80 mL of the 6% solution </span>
<span>C. 140 mL of the 3.5% solution and 60 mL of the 6% solution </span>
<span>D. 120 mL of the 3.5% solution and 80 mL of the 6% solution
</span>
Let fraction of 3.5% in final solution be p.
<span>p * 3.5 + (1 - p) * 6 = 4.5 </span>
<span>3.5p + 6 - 6p = 4.5 </span>
<span>2.5p = 1.5 </span>
<span>p = 3/5 </span>
<span>3/5 * 200 = 120 </span>
<span>Therefore the answer is B. 120 ml of 3.5% and 80 ml of 6%.</span>