10т-7ц 35кг-9ц 78кг

To simplify the expression "10т - 7ц + 35кг - 9ц + 78кг", we first need to convert all units to either tons (т), centners (ц), or kilograms (кг) for easier calculation. Here are the conversion factors you may need:

1 ton (т) = 100 centners (ц)
1 centner (ц) = 100 kilograms (кг)

Let's convert everything to kilograms (кг):

1. 10 tons (т) = 10 × 1000 kg = 10,000 kg
2. 7 centners (ц) = 7 × 100 kg = 700 kg
3. 35 kilograms (кг) = 35 kg (already in kg)
4. 9 centners (ц) = 9 × 100 kg = 900 kg
5. 78 kilograms (кг) = 78 kg (already in kg)

Now we can rewrite the expression using kilograms:

\[ 10,000 \text{ kg} - 700 \text{ kg} + 35 \text{ kg} - 900 \text{ kg} + 78 \text{ kg} \]

Now, let's perform the calculations step by step.

1. \( 10,000 \text{ kg} - 700 \text{ kg} = 9,300 \text{ kg} \)
2. \( 9,300 \text{ kg} + 35 \text{ kg} = 9,335 \text{ kg} \)
3. \( 9,335 \text{ kg} - 900 \text{ kg} = 8,435 \text{ kg} \)
4. \( 8,435 \text{ kg} + 78 \text{ kg} = 8,513 \text{ kg} \)

The final result of the expression \( 10т - 7ц + 35кг - 9ц + 78кг \) is:

8,513 kg.