- A
- B
- C
- D
Step-by-Step Solution
84 = . The trap is stopping the tree while a branch is still composite — 42, 21 and 4 can each be broken down further, so those rows are unfinished, not wrong sums.
Answer: A)
Anil draws a factor tree for 84. Which row shows his tree carried all the way down to prime numbers only?
Class 6Playing with NumbersPlaying with Numbers
Key idea: Prime vs composite
A whole number greater than 1 is **prime** if it has exactly two factors: 1 and itself. It is **composite** if it has more than two factors. The number 1 is neither prime nor composite (it has only one factor — itself). 2 is the only **even** prime; every other even number is divisible by 2 and so has at least three factors.
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