Ladybirds in the Garden

In Sam and Jill's garden there are two sorts of ladybirds with 7 spots or 4 spots. What numbers of total spots can you make?
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

Problem

Ladybirds in the Garden printable sheet

In Sam and Jill's garden there are two types of ladybirds. There are red Seven-Spot ladybirds with 7 black spots and black Four-Spot ladybirds with 4 red spots.

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Ladybirds in the Garden

Sam and Jill looked at a leaf with three ladybirds on it.

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Ladybirds in the Garden

"One Seven-Spot ladybird," said Sam, "and two Four-Spot ones."

"That's 15 spots altogether!" said Jill.

"I wonder if we could find ladybirds whose spots add to other numbers. I know how to do 16."

"And 14 is easy too," added Sam.

How would you make 16 and 14 spots with the Seven-Spot and Four-Spot ladybirds?

What other numbers can you make with adding 4s and 7s?

Can you get lots of numbers from 4 to 35?

Are there some numbers you can't get?