Question

tell the value for the variable.

1. $a + 12 = 27$
2. $35 - b = 32$
3. $\frac{1}{5}+\frac{2}{5}=c$
4. $8cdot6 = d$
5. $mdiv9 = 7$
6. $\frac{1}{10}cdot\frac{3}{4}=p$

activity 2
determine the ratio for each word problem.

1. there are 25 students in the class and 15 are boys. what is the boy - to - girl ratio?
2. in a survey of 100 students, 67 watch tv every night. what is the ratio of students who watch tv every night to total students?
3. there are 302 students in the freshman class. of the students, 150 are taking algebra and 152 are taking geometry. what is the ratio of students taking algebra to students taking geometry?

Explanation:

Activity 1

Problem 1:

Step1: Isolate variable a

Subtract 12 from both sides: $a=27 - 12$

Problem 2:

Step1: Isolate variable b

Rewrite as $b = 35-32$

Problem 3:

Step1: Add fractions

Since denominators are the same, add numerators: $c=\frac{1 + 2}{5}$

Problem 4:

Step1: Multiply numbers

$d=8\times6$

Problem 5:

Step1: Isolate variable m

Multiply both sides by 9: $m=7\times9$

Problem 6:

Step1: Multiply fractions

Multiply numerators and denominators: $p=\frac{1\times3}{10\times4}$

Activity 2

Problem 1:

Step1: Find number of girls

Number of girls is $25 - 15=10$. Boy - to - girl ratio is $\frac{15}{10}$

Problem 2:

Step1: Write ratio

Ratio of students who watch TV every night to total students is $\frac{67}{100}$

Problem 3:

Step1: Write ratio

Ratio of students taking algebra to students taking geometry is $\frac{150}{152}$

Answer:

Activity 1

1. $a = 15$
2. $b = 3$
3. $c=\frac{3}{5}$
4. $d = 48$
5. $m = 63$
6. $p=\frac{3}{40}$

Activity 2

1. $\frac{15}{10}=\frac{3}{2}$
2. $\frac{67}{100}$
3. $\frac{150}{152}=\frac{75}{76}$