You may also like

problem icon

Biscuit Decorations

Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?

problem icon

Constant Counting

You can make a calculator count for you by any number you choose. You can count by ones to reach 24. You can count by twos to reach 24. What else can you count by to reach 24?

problem icon

Skip Counting

Find the squares that Froggie skips onto to get to the pumpkin patch. She starts on 3 and finishes on 30, but she lands only on a square that has a number 3 more than the square she skips from.

Same Length Trains

Stage: 1 Challenge Level: Challenge Level:1

Thank you for your responses to this problem. Particularly good explanations were sent from Danny who goes to High Ash School, Shubha from Northveil Elementary and Abhijit from Bhavans School. Danny said:

First, we counted how many squares made up the train. $20$.

Then we worked out that we could use $10$ red rods, each of length $2$, to make a train of length $20$.
Then we used $5$ pink rods each of length $4$.
Then $4$ yellow rods each of length $5$.
Then $2$ orange rods each of length $10$.

Shubha gave a little bit more detail:

You have to look at the multiplication tables for the numbers $1$ through $10$.
Find all the combinations that have an answer of $20$. They are $1 \times 20$ = $20$; $2 \times 10$ = $20$; $4 \times 5$ = $20$; $5 \times 4$ = $20$; $10 \times 2$ = $20$
This means that by using the following combinations we can make the train length to be $20$ blocks:
$20$ rods that have a length of $1$ block
$10$ rods that have a length of $2$ blocks
$5$ rods that have a length of $4$ blocks
$4$ rods that have a length of $5$ blocks
$2$ rods that have a length of $10$ blocks
So it means that you can only make $5$ different trains of the same length as Matt's train.

(The first train you mention, Shubha, has already been made by Katie in the question, so there are four others as Danny concluded.) Well done to you all.