139 is suppose to be 140 and 18 is suppose to be 20, 140 x 20 = 2800
Home this works
Yes ok it is with a common
51 degrees should be the correct answer

The value of
.


We know that,

➪ 125° +
+ 30° = 180°
➪
+ 155° = 180°
➪
= 180° - 155°
➪
= 25°
Therefore, the value of
is 25°.
Now, the three angles of the triangle are 125°, 25° and 30°.

✒ 125° + 25° + 30° = 180°
✒ 180° = 180°
✒ L. H. S. = R. H. S.


Answer:
20 students
Step-by-step explanation:
If the class decreased by 15%, the students that she has now (17) represents a percentaje of:
100% - 15% = 85%
so<u> the 17 students are 85% of what she had</u>:
Students Percentage
17 ⇒ 85%
and we are looking for how many students she had 2 years ago, thus we are looking for the <u>100%</u> of students (the original number of studens). If we represent this number by x:
Students Percentage
17 ⇒ 85%
x ⇒ 100%
and we solve this problem using the <u>rule of three</u>: multiply the cross quantities on the table( 17 and 100) and then divide by the remaining amount (85):
x = 17*100/85
x = 1700/85
x=20
2 years ago she had 20 students