Answer: -70 is greater.
Step-by-step explanation:
When it comes to negatives, the larger number, -70 4/5, is ALLWAYS less and therefore had the least worth/definitely not the greatest. The lower a negative number is compared to another negative number, the "greater" it is due to it being closer to zero then the other number. In this case, -70 is closer to zero then -70 4/5 is.
Hope this helps.