## Prealgebra (7th Edition)

If we use the conversion rate given in the exercise is: $15\text{ st } 10\text{ lb}= 15\times 14 \text{ lb}+10 \text{ lb}=220 \text{ lb}$ Now we can convert from pounds to kilograms to check the equivalency, we have to consider the following conversion rate: $2.20\text{ lb}\approx 1 \text{ kg}$ After dividing both sides by $2.20$ we get: $1\text{ lb}\approx\frac{1}{2.20} \text{ kg}$ We multiply both sides by 220 in order to get the answer to the question: $220 \text{ lb} \approx \frac{220}{2.20}\text{ kg}= 100 \text{ kg}$ Yes, 100 kg is approximately 15 stone and 10 pounds.