Understanding Ratios for 5-Year-Olds: The Simple Problem of Two Numbers Summing to 72

This lesson helps a 5-year-old understand ratios through a fun and simple problem involving two numbers that add up to 72.

Understanding the Problem

Alright, let’s solve a fun little puzzle together! We have two numbers that are in a ratio of 2:1. This means if one number is big, the other number is smaller, and the big number is twice as big as the small number!

Step 1: Let’s Think About the Numbers

Let’s call the big number A and the small number B.

Since the ratio is 2:1, we can say:

  • A = 2B (the big number is two parts)
  • B = B (the small number is one part)

Step 2: The Sum of the Numbers

Now, we know that when we add both of these numbers together, we get 72:

A + B = 72

Step 3: Substituting the Big Number

We can replace A in the sum with 2B:

2B + B = 72

Now, let’s put together the big parts:

3B = 72

That means we have three of the small numbers!

Step 4: Finding B

To find out what one part (the small number B) is, we can divide 72 by 3:

B = 72 ÷ 3

B = 24

So the small number is 24!

Step 5: Finding A

Now, we can find the big number A using the small number:

A = 2B

A = 2 × 24 = 48

So the big number is 48!

Step 6: Check Our Work

Let’s check our numbers: 48 + 24 = 72. It works!

Conclusion

So the two numbers we found are:

  • Big number (A) = 48
  • Small number (B) = 24

Ask a followup question