Răspuns:
8052
Explicație pas cu pas:
Al treilea termen al unei progresii aritmetice:
T (n) = a + (n - 1) d
Unde ;
a = primul termen; d = diferență comună = 4; n = al treilea termen (numărul termenului)
Al treilea (3) termen:
T (3) = a + (3-1) 4
T (3) = 12
12 = a + 2 (4)
12 = a + 8
12 - 8 = a
4 = a
Prin urmare, primul termen = a
Al 2013-lea mandat;
T (2013) = a + (2013-1) d
T (2013) = 4 + (2012) 4
T (2013) = 4 + 8048
= 8052
In a triangle, the total angle is 180 degrees. A straight line is always 180 degrees. With this in mind, the following can be obtained:

These are simultaneous equations.

Answer:
18.0
Step-by-step explanation:
Note the tenth place value (underlined and bolded): 18.<u>0</u>49
Look at the number to the direct right of the tenth place value (or the hundredth place value in this case). It is a 4.
Note the rules of rounding. If the number:
1) is 5 or greater, round up.
2) is 4 or less, round down.
In this case, it is 4, so you will round down.
18.049 rounded to the nearest tenth is 18.0
~
Answer:
56.7
Step-by-step explanation:
We know
mean = sum / count, with count being the amount of papers corrected in this case. We want to find the sum of all the papers as well as the count to figure out the mean of all papers.
For Tony's papers,
mean = sum / count
50 = sum / 40
multiply both sides by 40 to isolate the sum
sum = 50 * 40 = 2000
For Alice's papers,
mean = sum / count
70 = sum / 20
multiply both sides by 20 to isolate the sum
70 * 20 = sum = 1400
The total sum of all 60 papers is equal to the sum of 40 papers + the sum of the remaining 20 papers, or 2000 + 1400 = 3400. The mean of the 60 papers is therefore
mean = sum / count
mean = 3400/60 ≈ 56.7