Answer:
15 cakes can be decorated.
Explanation:
Given:
Total number of shapes Liu has = 140
Ratio of shape of stars and hearts = 4 : 3
According to the question:
Each cake have 5 stars and 4 hearts.
Let the number of starts be "4x" and number of hearts be "3x" from the ratio.
Now,
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⇒

⇒

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Number of stars =

Number of hearts =

Each cake have 5 stars and 4 hearts .
How many cakes can be decorated with 80 stars.
⇒ No.of cakes = Total number of stars / 5
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How many cakes can be decorated with 60 hearts.
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But both shapes are in combination so only 15 cakes can be decorated with the combination of 5 stars and 4 hearts.
Liu can decorate 15 cakes and only.