Tool/Calculator to find missing number/fill the blanks puzzles/equations (addition, subtraction, multiplication, division)
Missing Numbers Calculator - dCode
Tag(s) : Number Games, Arithmetics
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A calculation with blanks (such as an addition, a subtraction, a multiplication, or a division) is a math exercise that involves finding the missing numbers and digits.
There is a variant where the operators (+ - * /) are missing.
Solving a calculation with operators and missing digits is similar to a cryptarithm and uses deduction and extraction of parts of the calculation.
Example: Exercise: find ? in the operation ??5 + 42? = 539 => 115 + 424 = 539
Example: 12 + 23 = ? has no solution but 12 + 23 = ?? has for solution 12 + 23 = 35
It is useful to calculate digits at extremities, or check individually calculations to the ten digits, or the hundreds digit etc.
dCode also has a cryptarithm solver (where blanks are letters), a mathematical equation solver or even a countdown game calculator tool.
dCode solver allow usual operators like additions +, subtractions -, multiplications * and divisions /. It also handles comparison operators superior and inferior > and < in addition to the equal sign =.
The blanks (unknown digits) have to be replaced by ? (interrogation marks). There is no limit but above 7 or 8, the calculation will be very long.
Example: 1+?=3 is solved with 1+2=3
Example: 2*?=8 is solved with 2*4=8
This solver uses a brute-force method, this means that it tries all combinations and display the possible ones.
If the message 0 solution(s) is displayed, it is impossible to replace the ? by numbers so that the calculation is valid. Several explanations:
— the ? is a number (consisting of several digits)
Example: 5+?=23 has no solution, but 5+??=23 does have the solution 18
— the ? is a negative number
Example: 5+?=1 has no solution but 5+-?=1 has a solution of 4
— an error may be in the problem statement
Fill in the blanks puzzles can help users improve their math skills. By solving these calculations, users can improve their understanding of basic math rules and improve their solving speed.
Point calculations sometimes cause problems due to the way languages handle floating point numbers. The IEEE 754 standard uses a binary representation to store floating point numbers, but it cannot store all floating point numbers exactly. Therefore, when a floating point number is stored, there may be a small loss of precision. This loss of precision can lead to miscalculations when floating point numbers are used in complex mathematical calculations.
dCode retains ownership of the "Missing Numbers Calculator" source code. Any algorithm for the "Missing Numbers Calculator" algorithm, applet or snippet or script (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, breaker, translator), or any "Missing Numbers Calculator" functions (calculate, convert, solve, decrypt / encrypt, decipher / cipher, decode / encode, translate) written in any informatic language (Python, Java, PHP, C#, Javascript, Matlab, etc.) or any database download or API access for "Missing Numbers Calculator" or any other element are not public (except explicit open source licence like Creative Commons). Same with the download for offline use on PC, mobile, tablet, iPhone or Android app.
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