Explore it
More pieces. The same amount.
Split each half into smaller equal pieces. Both bars represent the same-sized whole.
1/2 = 2/4
(1 × 2) / (2 × 2) = 2/4
The shaded length never changes. Both the shaded parts and the total parts are multiplied by 2.
Look a little closer
New names for the same amount.
Start with 1/2 of a bar. Split each half into 2 equal pieces. The whole now has 4 parts, and 2 are shaded.
You have not added or removed any of the bar. That is why 1/2 = 2/4. These are called equivalent fractions.
In numbers: multiply both the numerator and denominator by 2. Multiplying only one of them would change the amount.
Give the idea a try.
Take your time. Each answer comes with an explanation, and you can try again.