.
Let "a" be the number of adults; then the number of children is (2a).
The number of students is the rest, (207-a-2a) = 207-3a.
The "money" equation is
12a + 5*(2a) + 7*(207-3a) = 1498 dollars.
Simplify and solve for "a".
12a + 10a + 7*207 - 21a = 1498,
a = 1498 - 7*207
a = 49.
ANSWER. 49 adults; 2*49 = 98 children and (207-3*49) = 60 students.
Solved.
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This problem is to be solved using one equation in one unknown.
If you want to see many other similar solved problems, look into the lessons
- Advanced word problems to solve using a single linear equation
- HOW TO algebreze and solve these problems using one equation in one unknown
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