Question

the dot plot shows the birth year of everyone who works at sam’s office. the youngest person who works there was born in 1987. sam described the data as having a spread from 1965 to 1987, four gaps, a peak at 1984, and a center of 1978. where did sam make an error? birth year of employees dot plot with years 1965, 1970, 1975, 1980, 1985, 1990 options: the spread is from 1966 to 1987. there are 5 gaps. the peak is at 1985.

Explanation:

Step1: Analyze Spread

The youngest is 1987, but the leftmost dot (oldest) is at 1966 (since 1965 has no dots, first dots at 1966? Wait, no, looking at the dot plot: the first cluster starts at 1966? Wait, the x - axis has 1965, then the first dots are at 1966? Wait, no, the dot plot: the first set of dots is after 1965, so the minimum (oldest) birth year is 1966, not 1965. So the spread should be from 1966 to 1987, not 1965 to 1987. Let's check other options: gaps: let's count the gaps between clusters. Clusters: 1966 - 1969, 1970 - 1971 (no, 1970 has 2 dots, then gap to 1974 - 1975? Wait, maybe better to check the spread first. The first dot is at 1966 (since 1965 has no dots), so the minimum is 1966, maximum 1987. So Sam's error is in the spread: he said 1965 - 1987, but it's 1966 - 1987.

Step2: Check Other Options

• For "There are 5 gaps": Let's count gaps. Between 1969 - 1974: gap, 1971 - 1974: gap? Wait, maybe not. The first cluster: ~1966 - 1969, then gap to 1970 (2 dots), then gap to 1974 - 1979? No, maybe the spread error is more obvious. The peak: the tallest cluster is at 1984? Wait, the dot plot: the cluster at 1984 (around 1984 - 1985) – wait, the peak is at 1984? But the option says peak at 1985, but the main error is the spread. Wait, no, let's re - examine. The first dot (minimum) is at 1966 (since 1965 has no dots), so the spread is from 1966 to 1987, not 1965 to 1987. So the error is in the spread statement.

Answer:

A. The spread is from 1966 to 1987.