The mass lost by Darragh's coin is 0.164 g
<u>Solution:</u>
Given that Darragh has a Golden Eagle coin in his collection with a mass of 13.551 g
An uncirculated Golden Eagle coin has a mass of 13.715 g
To find: mass lost by Darragh's coin
From given question,
Darrangh has coin of mass = 13.551 g
Golden Eagle coin mass = 13.715 g
Darrangh's coin lost mass = 13.715 - 13.551 = 0.164
Thus mass lost by Darragh's coin is 0.164 g
Answer:
unreadable score = 35
Step-by-step explanation:
We are trying to find the score of one exam that is no longer readable, let's give that score the name "x". we can also give the addition of the rest of 9 readable s scores the letter "R".
There are two things we know, and for which we are going to create equations containing the unknowns "x", and "R":
1) The mean score of ALL exams (including the unreadable one) is 80
so the equation to represent this statement is:
mean of ALL exams = 80
By writing the mean of ALL scores (as the total of all scores added including "x") we can re-write the equation as:

since the mean is the addition of all values divided the total number of exams.
in a similar way we can write what the mean of just the readable exams is:
(notice that this time we don't include the grade x in the addition, and we divide by 9 instead of 10 because only 9 exams are being considered for this mean.
Based on the equation above, we can find what "R" is by multiplying both sides by 9:

Therefore we can now use this value of R in the very first equation we created, and solve for "x":

2.65/5=.53(price per pound)
.53*2lbs=1.06
a 2 lb bag will cost $1.06
The solution to the given system of equation is (25/7, 6/7)
<h3>System of equation</h3>
Given the system of equation expressed as:
x= - 4y+7 ........... 1
-2y+3x=9 ...........2
Substitute the equation 1 into 2 into have:
-2y + 3(-4y+7) = 9
-2y + 3(-4y) + 3(7) = 9
-2y - 12y + 21 = 9
Collect the like terms
-14y = 9- 21
-14y = -12
y = 6/7
Substitute y = 6/7 into equation 1;
x =-4y + 7
x = -4(6/7) + 7
x= -24/7 + 7
x = -24+49/7
x = 25/7
Hence the solution to the given system of equation is (25/7, 6/7)
Learn more on system of equation here; brainly.com/question/14323743
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