Each time Caroline goes shopping she decides whether or not to buy fruit. The probability that she does buy fruit is 0.4.
Independently, she then decides whether or not to buy a CD, with a probability of 0.3 that she does buy a CD.
Work out the probability that she buys fruit or buys a CD or both.

 0.58

Step-by-step explanation:

Step 1 : Caroline buys fruit and buys cd ( buys both) = 0.12      ( 0.4 x 0.3)

Step 2 : Caroline buys fruit and not cd =  0.28                          ( 0.4 x 0.7)

Step 3 : Caroline doesn't buy fruit but buys cd = 0.18               ( 0.6 x 0.3 )

STEP 4 (FINAL STEP) : Add all the probabilities ( 0.12 + 0.28 + 0.18)

0.58

Step-by-step explanation:

Step 1 : Caroline buys fruit and buys cd ( buys both) = 0.12      ( 0.4 x 0.3)

Step 2 : Caroline buys fruit and not cd =  0.28                          ( 0.4 x 0.7)

Step 3 : Caroline doesn't buy fruit but buys cd = 0.18               ( 0.6 x 0.3 )

STEP 4 (FINAL STEP) : Add all the probabilities ( 0.12 + 0.28 + 0.18)

ANSWER =  0.58

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.