Sun protection - is spf 50 better than spf 30

Yes SPF 50 is better than SPF 30 because SPF 50 increases the time you can spend out in the sun without sun cream. SPF 50 increases the amount of time you can spend out in the sun by 50 i.e the amount of time you can spend in the sun normally x 50 = n

but 50 doesn't block out more UV than 30

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