A scientist took a sample of spiny lumps (a type of fish) and found this sample to have a mean length of 2.5 cm. It is estimated that 16% of spiny lumps have a length of 4 cm or greater. What is the standard deviation of the lengths of this sample of spiny lumps?

1

2.25

1.5

0.5

0.75

The average human heart beats 72 beats per minute. how many times does it beat in 15 seconds?

1. if we have 3 babies what is the probability they’re going to be all boys? 2. if we roll 2 die at the same time what is the probability of getting less than 10 on the first roll and a 5 on the second roll 3. if we have 3 babies what is the probability their is going to be 2 girls? 4. if we have 3 babies what is the probability of having no more than 1 girl? 5. it we have 3 babies and then have another 3 babies what is the probability of us having at least 1 boy and then having all girls?

Need plz been trying to do it for a long time and still haven’t succeeded