Below are the dimensions of an assortment of rectangles. Which rectangle has dimensions that are similar to a rectangle that has a dimension 2 times 5? Assume that all the units are identical.

5 times 8
6 times 9
4 times 10
1 times 10
8 times 20
10 times 4

To determine which rectangle has dimensions that are similar to a rectangle with dimensions 2 times 5, we need to compare the ratios of the sides.

The ratio of the sides of a rectangle with dimensions 2 times 5 is 2:5.

Now, let's calculate the ratios for each given rectangle:

1. Rectangle with dimensions 5 times 8. The ratio is 5:8.
2. Rectangle with dimensions 6 times 9. The ratio is 6:9, which can be simplified to 2:3.
3. Rectangle with dimensions 4 times 10. The ratio is 4:10, which can be simplified to 2:5.
4. Rectangle with dimensions 1 times 10. The ratio is 1:10.
5. Rectangle with dimensions 8 times 20. The ratio is 8:20, which can be simplified to 2:5.
6. Rectangle with dimensions 10 times 4. The ratio is 10:4, which can be simplified to 5:2.

From the given rectangles, the ones with ratios that match the ratio of 2:5, which are similar to the rectangle with dimensions 2 times 5, are:
- Rectangle with dimensions 4 times 10
- Rectangle with dimensions 8 times 20

These two rectangles have sides that are in the same ratio as the rectangle with dimensions 2 times 5.