Challenge 2: Filter and Transform — Possible Solution
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use strict;
use warnings;
use feature 'say';

my @numbers = (1..10);

my @big = grep { $_ > 5 } @numbers;
my @doubled = map { $_ * 2 } @big;

say "@doubled";

Output:
12 14 16 18 20

WHY THIS WORKS AS AN ANSWER
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my @numbers = (1..10); reuses the range operator from Course 1's own
loop-range coverage to build the list 1 through 10 in one expression.

grep { $_ > 5 } @numbers reuses the chapter's own grep filtering
pattern exactly — $_ (the implicit topic variable) is set to each
number in turn, and only numbers where $_ > 5 is true survive,
producing (6, 7, 8, 9, 10), matching the chapter's own description of
grep as "keeps only the elements where the block evaluates true."

map { $_ * 2 } @big reuses the chapter's own map transformation
pattern directly, applied to the already-filtered @big list rather
than the original @numbers — doubling each of the five remaining
numbers produces (12, 14, 16, 18, 20).

Doing this as two separate steps (grep first, into @big, then map
into @doubled) rather than one chained pipeline keeps each step's
result independently inspectable, though the chapter's own chained
map/grep/sort pipeline shows this same two-step logic can also be
written as a single expression once each individual piece is
comfortable on its own.