Ajewellery shop is having a sale. a bracelet is now reduced to ? 420 this is 70% of the original price. a) work out the the original price

$600

Step-by-step explanation:

We can write a proportion. We know that $420 is 70% of an unknown original price. Let's call it x. We write equal ratios of comparing percent and comparing the $420 to the original price. We then set them equal.

We then cross multiply across the equal sign from numerator to the opposite numerator.

70(x)=420(100)

70x=42000

We divide to find x.

x=600.

80%

step-by-step explanation:

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)