How does a human do arithmetic calculation as fast as a calculator?
Use a tech called Mental abacus. When a person reads the numbers, he or she will mentally visualize an abacus and do the calculation by moving the beads in the abacus. The calculation can be done in a great speed.
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.
### Instruction: How does a human do arithmetic calculation as fast as a calculator?
### Input: 
### Response: Use a tech called Mental abacus. When a person reads the numbers, he or she will mentally visualize an abacus and do the calculation by moving the beads in the abacus. The calculation can be done in a great speed.