First i will build the envelope. for this, i am using a rectangular piece of material 28m long and 12m wide. out of this material, i have to cut patches that are 1/12 the length and 2/15 the width of the whole material. what is the area of a patch and how many such patches can i make out of the whole material?

3.728 cm²

90

Step-by-step explanation:

To built the envelope I am using a rectangular piece of material 28 m long and 12 m wide.  

Out of this material, I have to cut patches that are 1/12 the length and 2/15 the width of the whole material.

So, the length of the patches is m and the width of the patches is m.

Therefore, the area of the patches is (1.6 × 2.33) = 3.728 m² each. (Answer)

Now, the area of the rectangular piece of material is (28 × 12) = 336 m²

Hence, ≈ 90 such patches can be made out of the whole material. (Answer)

51840000 cm 2

step-by-step explanation: