Company A has a P/E of 15x and acquires Company B with a P/E of 10x using 100% stock. Is this deal accretive or dilutive, and why?

公司A的市盈率是15倍，现在打算全股票收购市盈率为10倍的公司B。不考虑溢价，这笔交易对公司A是增厚还是摊薄？为什么？