Answer: 7
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Step-by-step explanation:
The key states
It means that a stem of 7 and leaf of 4 combine to the value 74
We're interested in scores greater than 90, so we'll be focusing on the stems of 9 and 10 only
- Stem 9. Leaves 1,2,3,4,6,7.
- Stem 10. Leaf 0
Stem9 has 6 leaves while stem10 has 1 leaf. That's 6+1 = 7 leaves total, which means we have 7 scores above 90. If there was a leaf of 0 for stem9, then we'd have to ignore it (since it forms the score 90). But we don't have to worry about that for this case.