.
From the condition, you have this equation
0.35x = 12,
where "x" is the class population.
From the equation,
x = = 34.29 (approximately).
Rounding the answer to the nearest integer, you get the ANSWER : total number of students in the class is 34.
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In my view, the problem formulation IS NOT PERFECT.
When I read it for the first time, I may get understanding that 12 is the total number of students in the class.
Only when I read the second phrase, I start understand that it is not so.
Therefore, from my point of view, the problem, as it is presented, does not pass the test for accuracy . . .
Math problem should be presented / formulated in a more accurate way . . .
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This problem is on proportions.
On proportions, see the lessons
- Proportions
- Using proportions to solve word problems
- Using proportions to solve word problems in Physics
- Using proportions to solve Chemistry problems
- Typical problems on proportions
- Using proportions to estimate the number of fish in a lake
- HOW TO algebreze and solve these problems using proportions
- OVERVIEW of lessons on proportions
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