Post the situations maybe?
Answer:
x = 22 (see explanation!)
Step-by-step explanation:
Just with any algebraic equation, you will want to isolate the variable (x). Here's a step-by-step to show you how it's done:
1/7(x + 6) = 4
Multiply by 7 to get rid of the 1/7 (since 7 * 1/7 = 7/7 = 1)
7*1/7(x+6) = 7*4
x+6 = 28
Now, subtract 6 from both sides to isolate x:
x + 6 - 6 = 28 - 6
Finally:
x = 22
Answer: 55.56
Step-by-step explanation:
Let the unknown number be k
(45 x k) / 100 = 25
45k/100 = 25
multiply both sides by 100
45k = 25 x 100
45k = 2500
divide both sides by 45
k = 2500/45
k = 55.56
The lines that Mark drew are perpendicular.
Answer:
45 girls
Step-by-step explanation:
- Remark
- There are only 2 choices for gender. So if the class is 60% girls, the there must be 100 - 60 = 40% for the boys.
- But we are told that the boys are 30 in number.
- Let x = the total number of students.
Solution
- 40/100 * x = 30 Change the % to a decimal
- 0.4 x = 30 Divide both sides by 0.4
- 0.4 x / 0.4 = 30 / 0.4 Do the division
- x = 30/0.4
- x = 75 students in total
Formula
Total of Boys and Girls = Number of boys + number of girls.
Givens
- Total = 75
- Number of boys = 30
Solution II
- 75 = x + 30 Subtract 30 from each side
- 75 - 30 = x +30 - 30
- 45 = x
- There are 45 girls in the class.
