Answer:
<h3><em>
D. 880 = 45d + 70; 18 days.</em></h3>
Step-by-step explanation:
We are given fixed monthly charge = $70.
The cost of preschool per day = $45.
Number of days = d.
Total cost of d days = cost per day × number of days + fixed monthly charge.
Therefore, we get equation
880 = 45×d+70
<h3>880 = 45d +70.</h3>
Now, we need to solve the equation for d.
Subtracting 70 from both sides, we get
880-70 = 45d +70-70
810=45d
Dividing both sides by 45, we get

18=d.
Therefore,<em> 18 days Barry attended preschool last month.</em>
<em>Therefore, correct option is D option.</em>
<h3><em>
D. 880 = 45d + 70; 18 days.</em></h3>
Answer:

Step-by-step explanation:

Answer: There are 22.2 pounds of water in the bag.
Step-by-step explanation:
Hi, to answer this question we simply have to multiply the total weight of the bag by the water percentage in decimal form (divided by 100).
Mathematically speaking:
30 x (74/100) = 30 x 0.74 =22.2 pounds
There are 22.2 pounds of water in the bag.
Feel free to ask for more if needed or if you did not understand something.
Answer:ok
Step-by-step explanation:
If the ratio of red marbles to blue marbles in a jar is 3 to 8, the meaning is for every 3 red marbles there are 8 blue marbles.
3 red marbles------------------8 blue marbles.
ratio=3/8
we have 40 blue marbles; we have to compute the number of red marbles.
1) Method 1; by the rule three.
3 red marbles-----------------8 blue marbles
x----------------------------------40 blue marbles
x=(3 red marbles * 40 blue marbles) / 8 blue marbles=15 red marbles.
answer: B. 15
Method 2: the ratio of red marbles to blue marbles is
ratio=number of red marbles / number of blue marbles
ratio=3/8
if we want to compute the number of red marbles we have to multiply the number of blue marbles by this ratio.
number of red marbles=ratio (red/blue)* number of blue marbles
number of red marbles=(3/8)*40=15
Answer: B.15