Question

jada is making circular birthday invitations for her friends. the diameter of the circle is 12 cm. she bought 180 cm of ribbon to glue around the edge of each invitation. how many invitations can she make?

3 cards

7 cards

4 cards

5 cards

Explanation:

Step1: Find circumference of one invitation

The formula for the circumference of a circle is \( C = \pi d \), where \( d \) is the diameter. Given \( d = 12 \) cm, so \( C=\pi\times12\approx3.14\times12 = 37.68 \) cm.

Step2: Calculate number of invitations

Divide total ribbon length (180 cm) by circumference of one invitation. \( \text{Number}=\frac{180}{37.68}\approx4.77 \). Since we can't make a fraction of an invitation, we take the whole number part, which is 4.

Answer:

4 cards