1.667Use covered interest rate parity:F=S×1+r$1+r\£F = S \times \frac{1+r_{\$}}{1+r_{\£}}F=S×1+r\£​1+r$​​ Spot rate S=1.61S = 1.61S=1.61 US$/£US$ interest rate r$=10.18%=0.1018r_{\$} = 10.18\% = 0.1018r$​=10.18%=0.1018GBP interest rate r\£=6.4%=0.064r_{\£} = 6.4\% = 0.064r\£​=6.4%=0.064F=1.61×1.10181.064≈1.61×1.0355≈1.667F = 1.61 \times \frac{1.1018}{1.064} \approx 1.61 \times 1.0355 \approx 1.667F=1.61×1.0641.1018​≈1.61×1.0355≈1.667 Answer (to three decimal places):GBP1 = US$1.667\boxed{\text{GBP1 = US\$1.667}}GBP1 = US$1.667​