Let C = the Chinese books.
Let E = the English language books.
C = 4/5 E
E - 300 = C - 180 Notice how you get this equation. You take 300 away from the English books and 180 from the Chinese and according to the question, you get an equal number of both. Put c = 4/5E into the second equation.
E - 300 = 4/5 E - 180 Add 300 to both sides.
E = 4/5 E - 180 + 300
E = 4/5 E + 120 Now subtract 4/5 E from both sidies.
E - 4/5 E = 120
1/5 E = 120 Now multiply by 5
E = 120 * 5
E = 600
So the number of books are
600 written in English
4/5 of 600 = 2400 /5 = 480 Chinese books.
English 600
Chinese 480
Answer:
d. Since fertilizer is in both data sets and is positively correlated to both tree height and fruit yield, it is like that tree height and fruit yield are also positively correlated.
Step-by-step explanation:
The correlation refers to the relationship between two or more variables i.e how they are interrelated to each other. It can be positive, negative, perfect, etc
As we can see in the figure that in both the data sets the fertilizer contains the same values which depict that they are positively correlated with respect to the height of tree and fruit yield that derives that the height of tree and fruit yield is also positively correleated
Here positive correlation means that the two variables moving in a similar direction i.e if one variable increased so the other is also increased
Therefore the option d is correct
Answer:
x= 37.5°
Step-by-step explanation:
∠CBD
= 180° -75° (adj. ∠s on a str. line)
= 105°
∠BCD= ∠BDC (base ∠s of isos. △BCD)
∠BCD= x
∠BCD +∠BDC +∠CBD= 180° (∠ sum of △BCD)
x +x +105°= 180°
2x= 180° -105°
2x= 75°
x= 37.5°
<u>Alternative</u><u> </u><u>working</u><u>:</u>
∠BDA= (180° -75°) ÷2 (base ∠s of isos. △ABD)
∠BDA= 52.5°
∠BDA +∠BDC= 90°
52.5° +x= 90°
x= 90° -52.5°
x= 37.5°
