1. **State the problem:** We need to subtract two numbers in scientific notation: $7.26 \times 10^{-10}$ and $2.82 \times 10^{-11}$.\n\n2. **Rewrite the numbers with the same power of ten:** To subtract, express both numbers with the same exponent. The smaller exponent is $10^{-11}$, so rewrite $7.26 \times 10^{-10}$ as $72.6 \times 10^{-11}$.\n\n3. **Perform the subtraction:** Now subtract the coefficients: $$72.6 - 2.82 = 69.78.$$\n\n4. **Write the result in scientific notation:** The result is $69.78 \times 10^{-11}$. To express in standard scientific notation, move the decimal point one place to the left and increase the exponent by 1: $$6.978 \times 10^{-10}.$$\n\n5. **Final answer:** $$6.978 \times 10^{-10}.$$