## Solve this question: Can you make 100 by interspersing any number of pluses and minuses within the string of digits 9 8 7 6 5 4 3 2 1? You c

Question

Solve this question: Can you make 100 by interspersing any number of pluses and minuses within the string of digits 9 8 7 6 5 4 3 2 1? You can’t change the order of the digits! So what’s the least number of pluses and minuses needed to make 100? For instance, 98 – 7 – 6 + 54 – 32 shows one way of interspersing pluses and minuses, but since it equals 107, it’s not a solution.

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4 months 2022-01-21T11:02:29+00:00 1 Answer 0 views 0

98-76+54+3+21=100

• 1 Plus
• 3 Minuses

Step-by-step explanation:

Possible Variants are:

[tex]98 – 76 + 54 + 3 + 21 = 100\\9 – 8 + 76 + 54 – 32 + 1 = 100\\98 + 7 + 6 – 5 – 4 – 3 + 2 – 1 = 100\\98 – 7 – 6 – 5 – 4 + 3 + 21 = 100\\9 – 8 + 76 – 5 + 4 + 3 + 21 = 100\\98 – 7 + 6 + 5 + 4 – 3 – 2 – 1 = 100\\98 + 7 – 6 + 5 – 4 + 3 – 2 – 1 = 100[/tex]

[tex]98 + 7 – 6 + 5 – 4 – 3 + 2 + 1 = 100\\98 – 7 + 6 + 5 – 4 + 3 – 2 + 1 = 100\\98 – 7 + 6 – 5 + 4 + 3 + 2 – 1 = 100\\98 + 7 – 6 – 5 + 4 + 3 – 2 + 1 = 100\\98 – 7 – 6 + 5 + 4 + 3 + 2 + 1 = 100\\9 + 8 + 76 + 5 + 4 – 3 + 2 – 1 = 100\\9 + 8 + 76 + 5 – 4 + 3 + 2 + 1 = 100\\9 – 8 + 7 + 65 – 4 + 32 – 1 = 100\\[/tex]

From:

98-76+54+3+21=100

The least number of plus and minuses needed to make 100 are 1 and 3 respectively.