Answer
Since \$0.047/ounce is less than \$0.049/ounce, Dazzle is the better buy.
Work Step by Step
Since Dazzle is concentrated to wash twice as many loads, 64 ounces is equivalent of 128 ounces.
Dazzle $\frac{5.99}{128 ounces}$ = $\frac{5.99\div128}{128\div128 ounces}$ = $\frac{0.047}{1 ounce}$ = 0.047/ounce
Spot-B-Gone $\frac{7.29}{150 ounces}$ = $\frac{7.29\div150}{150\div150 ounces}$ = $\frac{0.049}{1 ounce}$ = 0.049/ounce
