Answer:
The plumber worked for 1.5 hours
Step-by-step explanation:
y = 130 + 56x
Substitute 214 for y in the equation
214 = 130 + 56x
-130 -130 Subtract 130 from both sides
84 = 56x Divide both sides by 56
1.5 = x
Answer:
First do the case in which none of the digits is 0.
There are 9 ways to choose the digit that repeats 3 times and 8 ways to pick the other, after this there are 4 ways to order the digits. So 9×8×4.
Now we look at the cases in which the digit 0 repeats 3 times. Clearly the 9 numbers are 1000,2000,3000,…,9000.
Lastly we look at the cases in which 0 appears once. There are 9 ways to pick the other digit and 3 ways to order.
So the final answer is 9×8×4+9+9×3.
Answer:
$68.97
Step-by-step explanation:
Markup is the difference between the cost of an item and the price at which it is sold:
cost price + markup = selling price
Here, the markup is said to be 70%. The base for that percentage can be either the cost price or the selling price. The way this question is worded suggests the markup is 70% of the cost price.
So, we have ...
cost price + 0.70 × cost price = selling price
or
cost price × (1 + 0.70) = selling price
__
Then, to find the cost price, we can divide by its coefficient in this equation. Doing that gives ...
cost price = (selling price)/1.70
cost price = $117.25/1.70 = $68.97
The store's purchase price before the markup for this item was $68.97.
Answer:
I love cats....... but I also love dogs
Step-by-step explanation:
Answer:
No this is a not good experimental design
Step-by-step explanation:
In an experiment, we seek to establish cause an effect relationship. The effect of one variable on another is examined while keeping other variables constant. A control often establishes the validity of the experiment.
Now the ten rubber bands were selected at random from each box. The experimental group was put in a freezer while the control group was maintained at room temperature.
Comparison of the mean stretch before breakage of the rubber bands in both groups establishes the effect of cold temperature on elasticity of rubber bands.
However, this is not a good experimental design because the sample rubber bands should have been picked from different boxes of brand A and B and not from the same box.
Secondly, samples from the two brands should have been put in the freezer and kept at room temperature. That is, ten rubber bands from A are put on the freezer and another 10 are left at room temperature. 10 rubber bands from B are put in the freezer and another 10 are left at room temperature.
The mean elasticity of the both groups can now be meaningfully compared from the data obtained.
