Answer:
C
Step-by-step explanation:
18 boys
- cos ( 1/2 x + 1/5 π ) = 0 ( and because if cos α = 0, α= π/2 + k π, k ∈ Z )
1/2 x + π/5 = π/2 + k π, k ∈ Z
1/2 x = π/2 - π/5 + k π / * 2
x = π - 2π/5 + 2 k π
x = 3/5 π + 2 k π = 0.6 π + 2 k π
Answer:
If k = 0: x 1 = 0.6 π = 3π/5
k = 1 : x 2 = 2.6 π = 13π/5
Answer:
As a fraction: 
As a colon, 363:2
By using the word to; we have: 363 to 2
Step-by-step explanation:
A ratio is a comparison of two quantities. We can write a ratio as a fraction, using the word “to,” or using a colon.
A rate is a ratio that compares two different units, such as distance and time, or a ratio that compares two different things measured with the same unit, such as cups of water and litres of petrol.
We can use a ratio to compare the number of days regardless of employing any professional sports events each year with the total number of days in a year.
The ratio with which we can write, that compares days with games in a year with two days without them can be written in three ways.
Suppose there are 365 days in a year and it appears that two days in that year exist without a game.
i.e.
365 - 2(days without game) = 363 days with a game
Then:
As a fraction: 
As a colon, 363:2
By using the word to; we have: 363 to 2
Answer:
There was once a duck, that ate many grapes. One day, there were 67 grapes. The next day there were 20 grapes left. How many grapes did the duck eat.
Step-by-step explanation:
67-20 = 47
Answer:
Step-by-step explanation:
1/2(10x-8)=1/3(21-15x)
Opening the brackets
5x - 4 = 7 - 5x
5x + 5x = 7 + 4
10x = 11
x = 11/10
x = 1 1/10