Kristen spent $25 to buy 9 flowers (F) for her mother on May 10. She bought roses (R) which cost $3 and daisies (D) which cost $2. How many roses and how many daisies did she buy.
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Total number of roses bougth
F= 9
F = R + D (I)
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total cost (C)
C= 25
C= R *3 + D*2 (II)
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Solving the two equations system by substitution
F = R + D
9= R + D
D= 9 - R
Replacing in (II)
25 = R *3 + (9 - R)*2 (II)
25 = 3*R + 18 - 2R
R = 25- 18
R=7
D= 2
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Answer
Kristen bought 7 roses and 2 daisies
