Consider the following:
We can form a simple equation to represent the total number of apples as:
4 + 5 = b
which can also be written as:
b = 4 + 5
which can also be written as:
n = 330 - 120
Newton had p mangoes.
Total number of mangoes was 45.
14 + p = 45.
p = 45 - 14
Tuesday: y bags
Total: 210 bags
90 + y = 210
y = 210 - 90
Ate: 4 mangoes
Arrived with 6 mangoes
The above equation can also be written as:
k = 6 + 4
Practice Example 1:
We can form a simple equation to represent the total number of apples as:
4 + 5 = b
which can also be written as:
b = 4 + 5
Practice Example 2:
The number of boys in a school is n. The number of girls in the same school is 120. If the total number of student in the school is 330, form a simple equation that can be used to find the value of n.Answer:
n + 120 = 330which can also be written as:
n = 330 - 120
Note
When we take the + 120 to the other side of the equation, the sign changes to minus (-) becoming - 120. The + and − signs change to the other when moved to either side of the equation.
When we take the + 120 to the other side of the equation, the sign changes to minus (-) becoming - 120. The + and − signs change to the other when moved to either side of the equation.
Practice Example 3:
John had 14 mangoes and Newton had p mangoes. If the total number of mangoes they had was 45, form a simple equation that can be used to find the value of p.Answer:
John had 14 mangoes.Newton had p mangoes.
Total number of mangoes was 45.
14 + p = 45.
p = 45 - 14
Practice Example 4:
The number of bags of beans harvest on Monday was 90. On Tuesday, y bags of beans were harvested. If the total number of bags harvested on Monday and Tuesday was 210, for a simple equation to show the number of bags harvested on Tuesday.Answer:
Monday: 90 bagsTuesday: y bags
Total: 210 bags
90 + y = 210
y = 210 - 90
Practice Example 5:
A grade 5 pupil in your school bought k mangoes from the market. On his was home, he ate 4 mangoes. If he arrived home with 6 mangoes, form a simple equation to show how many mangoes he bought from the marketAnswer:
Total number of mangoes: kAte: 4 mangoes
Arrived with 6 mangoes
If we subtract the number of mangoes he ate, from the total number of mangoes, we get the number of mangoes he was left with.
k - 4 = 6.The above equation can also be written as:
k = 6 + 4