Resources
Interactive online number line generator https://helpingwithmath.com/generators/numberlinegenerator01/
Solutions to selected problems from Problem Set I.
(1) Let x be the price of a container of ice cream in dollars; then,
4x + 10 = 20
4x = 20 - 10
x = (20 – 10) / 4 = 10 / 4 = 2.5 $
(3) Let x be the number of notebooks that Roger bought, then,
3x + 2 = 20
3x = 20 -2
x = (20 - 2) / 3 = 18 / 3 = 6 notebooks.
(7) Let x be the number of pages in the sticker book.
5x + 2 = 62
5x = 62 – 2
x = (62 – 2) / 5
x = 60 / 5 = 12 pages
(10) Let x be the number of bulbs in each row, then,
7x + 4 = 5(12)
7x + 4 = 60
7x = 60 – 4
x = (60 – 4) / 7
x = 56 / 7 = 8 bulbs in each row.
Solutions to selected problems from Problem Set II.
(1) Let x be the number of persons who will get some cake, then,
2/3 x + ¼ = 25 /4
2/3 x = (25 /4) – (1/4)
2/3 x = 24 /4
x = (24 /4) * (3/2) = 72 / 8 = 9 people.
(4) Let x be the price of one pound of grapes.
4/5 x + 2 = 10
4/5 x = 10 – 2
4/5 x = 8
x = 8 / (4/5) = (8 /1) / (4/5)
x = (8 /1) * (5/4) = 40 /4 = 10 $ / b
(6) Let x be the number of miles Peter swam.
And, time = speed * distance, then,
4/3 x + ½ = 3
4/3 x = 3 – ½ = 6 /2 – 1 /2
4/3 x = 5/2
x = (5/2) / (4/3)
x = (5/2) * (3/4) = 15/8 miles
(8) Let x be the number of tables Carlos set up, then,
(2/3) 4x + 20 = 60
8/3 x = 60 - 20
8/3 x = 40
x = (40/1) / (8/3)
x = (40/1) * (3/8) = 120 / 8 = 15 tables
Comments: