Lesson 5

Math 1

January 27, 2021

Example 1

A metal alloy weighing 12 kg and

containing 45% platinum is melted and mixed with 8 kg of a different alloy which contains 10% platinum. What percent of the resulting alloy is platinum?

Example 2

10 kg of fruit salad was made by

combining 8 kg of sliced peaches which cost $8/kg with 2 kg of sliced bananas which cost $3/kg. Find the cost per kg of the mixture.

Example 3

How many mg of a metal containing 70% nickel must be combined with 2 mg of pure nickel to form an alloy containing 75% nickel?

Example 4

How many gal. of a 15% acid solution must be mixed with 4 gal. of a 75% acid solution to make a 35% solution?

https://youtu.be/bknKLAnkIRo

Example 5

 $y\ge-\frac{9}{2}x-5$  

Example 6

 $y\le-3x+4$  

Example 7

 $x-5y\le-20$  

Example 8

 $5x+3y>6$  

Multiple Choice

What is the equation of the linear inequality seen in the graph?

•  $x+2y\le8$  

•  $x+2y\ge8$  

•  $x-2y\ge8$  

•  $x-2y\le8$  

Multiple Choice

The table below shows the population of a city x years since 1990. If the population continues to grow at a linear rate, what will be the approximate population in 2020?

• 41,400

• 45,700

• 51,300

• 56,800

Fill in the Blanks

Fill in the Blanks