Solving Equations/Inequalities

Pages 145 - 146

Application Problems

Amy earned a grade of 83 and 94 on her two math tests. What must she earn on her third test to get A average

Average = 90# of tests = 3Test Grades =83, 94

We know that

Given

Solution

𝑨𝒗𝒆𝒓𝒂𝒈𝒆=𝑺𝒖𝒎𝒐𝒇 𝒕𝒉𝒆𝒕𝒆𝒔𝒕𝒔

¿𝒐𝒇 𝒕𝒆𝒔𝒕𝒔

𝟗𝟎=𝟖𝟑+𝟗𝟒+𝒙

𝟑

Amy will have to earn 93 on her next test

Example 1:

Let missing test be x

270 = 177 + x

x = 93

Sum of three consecutive numbers is 129. Find the numbers

Sum of consecutive numbers = 129

We know that

Given

Solution

x, x+1, x+2

3x + 3 = 129

The numbers are 42, 43, 44

Example 2:

x+ (x+1) + (x+2) = 129

3x = 126

x = 42

Sum of three consecutive numbers is 129. Find the numbers

Sum of consecutive numbers = 129

We know that

Given

Solution

x, x+1, x+2

3x + 3 = 129

The numbers are 42, 43, 44

Example 3:

x+ (x+1) + (x+2) = 129

3x = 126

x = 42