I have a dataset. I want to add a calculated measure that gives the total cost for each set of rows grouped by CaseID. An example below shows the table layout, and the "Total Case Cost" column is the one i am trying to calculate. Can someone point
me in the right direction with the Dax? Ive tried using SUMMARIZE but cant get it to work:

CaseID |
TestCode |
BatchCode |
TestCost |
Total Case Cost |

A001 |
A1 |
A |
20 |
65 |

A001 |
A1 |
B |
20 |
65 |

A001 |
A2 |
A |
15 |
65 |

A001 |
A3 |
A |
10 |
65 |

A002 |
B4 |
A |
50 |
70 |

A002 |
B5 |
A |
20 |
70 |

Thanks!