Answer:
y=29
Step-by-step explanation:
Replace x with 7:
y=8+3(7)
Multiply 7 and 3:
y=8+21
Add together:
y=29
Answer:
33.33 mL of 50%
66.67 of 80%
Step-by-step explanation:
Let x = quantity of 50% methane.
Then,
0.50x + 0.80(100 - x) = 100 × 0.70
⇒ 0.50 x + 80 - 0.80 x = 70
⇒ -0.30 x = 70 - 80
⇒ -0.30 x = -10
⇒ 
⇒ x = 33.33 mL of 50%
and, 100 - 33.33 = 66.67 of 80%
Answer:
The number of tables were used that day at lunch is 23 tables.
Step-by-step explanation:
Given as :
The total number of students in the Polk school = 203
On one day the number of students absent = 19
So, The number of student present on that day = Total student - absent students
I.e The number of student present on that day = 203 - 19 = 184
The number of students sit on each table = 8
Let The number of tables were used that day at lunch = n
<u>So, According to question</u>
The number of tables were used that day at lunch = 
I.e n = 
∴ n = 23 tables
So, The number of tables were used that day at lunch = n = 23 tables
Hence, The number of tables were used that day at lunch is 23 tables. Answer