Parenthases
Equation
Multiplication
Division
Addition
Subtraction
Let number of fives = x then number of ones = 3x and number of tens = x - 1
so we can create the equation
x + 3x + x-1 + y = 26 where y = number of twenties
so
5x + y = 27
also we have the equation
5x + 3x + 10(x - 1) + 20y = 120
18x + 20y = 130..................................(1)
5x + y = 27 multiply by -20:-
-100x - 20y = -540..............................(2)
Adding equation (1) and (2)
-82x = -410
x = 5, that is 5 fives
Now plug x = 5 into equation 1:-
18(5) + 20y = 130
20y = 40
y = 2 , that is 2 twenties
So the answer is there are (3x) = 15 ones , 5 fives, 4 tens and 2 twenties
<span>A number is divisible by 9, if the sum is a multiple of 9 or if the sum of its digits is divisible by 9.
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