a 3'' times 5'' photo is enlarged so that the length of the new photo is 7 inches. what is the width of the new photo?

Use a proportion:

3/5 = x/7

Cross multiply and solve for x.

5x = 21

x = 21/5

x = 4.2"

To find the width of the new photo, we can use the concept of proportions.

We know that the length of the original photo is 3 inches and the length of the enlarged photo is 7 inches. Let's represent the width of the original photo as "x" inches, and the width of the enlarged photo as "y" inches.

Now, we can set up a proportion using the lengths of the original and enlarged photos:

3 inches (original length) / 7 inches (enlarged length) = x inches (original width) / y inches (enlarged width)

To solve for "y" (the width of the enlarged photo), we can cross-multiply and solve for "y":

3 * y = 7 * x

y = (7 * x) / 3

Now, we need one more piece of information to solve for "y". If we know the original width of the photo, we can substitute that value into the equation and find the width of the enlarged photo.

Unfortunately, you didn't provide the original width of the photo. Therefore, without this information, we cannot find the exact width of the enlarged photo.