Hello,
Here is the formula to find the area of the trapezoid:
A=1/2(b1+b2)×h
Where b1 represent big base
b2 represent small base
and h represent height
Now, we just need to replace the number to get the final answer:
A=1/2(16.8+6.9)×2
A=1/2(23.7)×2
A=23.7 square yards. As a result, the area of the trapezoid is 23.7 square yards. Hope it help!
Answer:

Step-by-step explanation:
![\text{Geometric mean:}\\\\\underbrace{\sqrt[n]{a_1\cdot a_2\cdot a_3\cdot...\cdot a_n}}_n\\\\\sqrt{7\cdot9}=\sqrt{9}\cdot\sqty7=3\sqrt7](https://tex.z-dn.net/?f=%5Ctext%7BGeometric%20mean%3A%7D%5C%5C%5C%5C%5Cunderbrace%7B%5Csqrt%5Bn%5D%7Ba_1%5Ccdot%20a_2%5Ccdot%20a_3%5Ccdot...%5Ccdot%20a_n%7D%7D_n%5C%5C%5C%5C%5Csqrt%7B7%5Ccdot9%7D%3D%5Csqrt%7B9%7D%5Ccdot%5Csqty7%3D3%5Csqrt7)
Her friend is right because 20% of $18.34 is $3.67.