Apartment shareholder be able to withdraw resources proportional to his share

Apartment.sol

function withdraw() public {
        require(this.balanceOf(msg.sender) > 0, "unauthorized");
        uint meansToWithdraw = address(this).balance / 100 * this.balanceOf(msg.sender);
        balance = balance - meansToWithdraw;
        payable(msg.sender).transfer(meansToWithdraw);
    }

    receive() external payable {
        balance += msg.value;
    }

index.ts

it("Apartment shareholder be able to withdraw resources proportional to his share", async () => {
    const Apartment = await ethers.getContractFactory("Apartment");
    const apartment = await Apartment.deploy();

    [owner, Alice, Bob] = await ethers.getSigners();

    await apartment.deployed();
    await apartment.transfer(Alice.address, 20);

    await Bob.sendTransaction({
      to: apartment.address,
      value: ethers.utils.parseEther("1")
    });

    const aliceBalanceBeforeWithdrawal = await Alice.getBalance();

    await apartment.connect(Alice).withdraw();
    expect(await (await apartment.balance()).eq(ethers.utils.parseEther("0.8"))).to.be.true;
    expect(await (await apartment.balance()).gt(ethers.utils.parseEther("0"))).to.be.true;
    expect(await (await Alice.getBalance()).gt(aliceBalanceBeforeWithdrawal)).to.be.true;




  })