Veg is one cup per per pig per day
Pellets are one tablespoon per pig per day. This is how you will see the advice everywhere on the forum.
We don’t tend to use cup measures in the UK (although we will refer to veg in cups as it’s easier due to the differing densities of vegetables).
It looks like google says 1/8 cup is two tablespoons so (if that is a correct conversion) then you can give 1/8 cup once a day for them to share, but they shouldn’t have 1/8 cup each as that could mean they are getting double the amount they should have. (As I say this is based on a google conversion as we do not really use cup measures here)
What is vital is that you don’t over feed pellets - you are better off to under feed them (there are some of us on here (myself included) who don’t feed pellets at all). Too many pellets can stop them eating enough hay but also pellets contribute a lot of calcium into the diet which can lead to poor bladder health (sludge and stone formation).
Provided you don’t over feed veg and pellets (which are purely supplementary in the diet and only jointly make 20% of their daily food intake (15% for veg and 5% for pellets, hay being 80%) then if their weights are going up (if they’re young) or stable (if they’re adult) then you will know are eating enough hay.
Weigh them once a week (or daily if you have heath concerns) to monitor their hay intake.
I’ve added weight guides below to help further.
You will see everything is referred to in grams. Google conversion says that 1.2lbs is around 540g so I’m guessing your piggies are babies.
Weight and Weight Loss Explained: BMI, Weighing, Poos and Feeding Support
The other thing to try to help them feel secure and settle is to cover half their cage. Piggies don’t like to feel exposed so clipping a blanket over one half of the cage and putting their hay under the covered side can help them feel safer.