SITUATION:
Ali read 9 pages of a story book on Monday. On Tuesday, he read a few pages more. The total of pages he has read is 20 pages.
Number of pages Ali read on Tuesday is unknown.
SOLUTION:
Monday: 9 pages
Tuesday: \(x\) pages (unknown)
Total pages: 20 pages
If we change to mathematic equation, we will get \(9 + x = 20\).
To find \(x\), we will subtract 9 from both parts of the equation.
\(9 \color{red}- \color{red}9 +x = 20 \color{red}- \color{red}9\)
\(x = 11\)
Therefore, \(x\) is 11.
Ali collects stamps. He gives 12 stamps to his brother. Ali now has 38 stamps.
Number of stamps Ali collects is unknown.
Stamps that Ali collect : \(y\) pieces
Stamps that Ali give to his brother: 12 pieces
Remainder of stamps that Ali have: 38 pieces
If we change to mathematic equation, we will get \(y - 12 = 38\).
To get \(y\), we will add 12 to both sides of the equation.
\(y -12 \color{red}+\color{red}1\color{red}2 = 38 \color{red}+\color{red}1\color{red}2\)
\(y = 50\)
Therefore, \(y\) is 50.
Assess yourself by staged practices
