Create a structure to store the product name, rate, and quality. Also, deduct a 10% discount on the total price if the total price exceeds 20,000.

Use a structure in C to store product name, rate, and quality, and apply a 10% discount if the total price exceeds 20,000.

To store product information including name, rate, and quality, a structure in C could be used. Here's an example:

#include <stdio.h>

struct Product {
    char name[50];
    float rate;
    int quality;
};

float calculate_discounted_price(float total_price) {
    if (total_price > 20000) {
        total_price -= total_price * 0.1; // Deduct 10% discount
    }
    return total_price;
}

int main() {
    struct Product product;

    // Example product setup
    strcpy(product.name, "ExampleProduct");
    product.rate = 10500; // rate per unit
    product.quality = 2; // number of units

    float total_price = product.rate * product.quality;
    float discounted_price = calculate_discounted_price(total_price);

    printf("Product: %s\n", product.name);
    printf("Total Price: %.2f\n", total_price);
    printf("Discounted Price: %.2f\n", discounted_price);

    return 0;
}

In this program, a structure Product is used to store the product's name, rate, and quality. The calculate_discounted_price function applies a 10% discount if the total_price exceeds 20,000.