One answer is a place to start
A second right answer is a different answer that also fits every rule. Most of us find one answer and stop there.
Finding the second is a habit. After any correct answer, ask "what else works?" before you move on.
To look, change one thing: the order, the grouping or the operation. Then check that the new answer still fits every rule. If it does, you have a second right answer.
1Find one answer that fits.
2Ask: what else works?
3Change one thing, then check every rule again.
Three ways to 24
Make 24 from 1, 2, 3 and 4, using each number once.
First way: 1 × 2 × 3 × 4 = 24.
Change the operation on the first three numbers: 1 + 2 + 3 is 6, and 6 × 4 is 24. That is (1 + 2 + 3) × 4.
Change the grouping: 4 + 2 is 6, 3 + 1 is 4, and 6 × 4 is 24. That is (4 + 2) × (3 + 1).
Same numbers, three right answers. Writing the first way in another order, such as 4 × 3 × 2 × 1, is the same answer, not a new one.
Find a second way
You have 1, 2, 3 and 4, and one way already: 1 × 2 × 3 × 4. Work out each choice before you pick.
Try it
Which is a second right answer?
- (1 + 2 + 3) × 4
- (1 + 2) × 3 × 4
Show the answer
(1 + 2 + 3) × 4
Right. 1 + 2 + 3 is 6, and 6 × 4 is 24. It uses each number once, so it fits every rule, and it is a different answer from 1 × 2 × 3 × 4.
Enable JavaScript to answer interactively and save your place.
Practice Make 24