SOLUTION: Ailing bought 3 similar big cakes and 4 similar small cakes . The total mass of the 7 cakes is 9.62kg. The mass of the big cake is twice the mass of the small cake. Find the total

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Question 890952: Ailing bought 3 similar big cakes and 4 similar small cakes . The total mass of the 7 cakes is 9.62kg. The mass of the big cake is twice the mass of the small cake. Find the total mass of the 4 small cakes in kg , correct to 1 decimal place
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39628) About Me  (Show Source):
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mass of small cake, y
mass of big cake, x

3%2Ax%2B4%2Ay=9.62 kg, accounting for mass of the bought seven cakes.

Mass relation description gives x=2y, but possible misunderstanding.

3x%2B4%282x%29=9.62
12x=9.62
x=9.62%2F12
x=0.8017, mass of one big cake.
-
y=x%2F2
but you want to know 4y, meaning FOUR of the small cakes mass.
4y=4%28x%2F2%29=4%280.8017%29%2F2
highlight%284y=1.603%29
To one decimal place, 1.6 kg.

Answer by MathTherapy(10556) About Me  (Show Source):
You can put this solution on YOUR website!

Ailing bought 3 similar big cakes and 4 similar small cakes . The total mass of the 7 cakes is 9.62kg. The mass of the big cake is twice the mass of the small cake. Find the total mass of the 4 small cakes in kg , correct to 1 decimal place


Mass of 1 small cake:  0.962 kg

Mass of 4 small cakes: 0.962(4), or 3.848 ≈ highlight_green%283.8%29%29 kg