456, because they are consecutive, 4+5+6 is equal to 15, which is smaller than 20 but larger than 10, and 5 (which is in the tens place) is odd. :)
95 eight 10's (80) three5s (15) 80 plus 15 is 95
If the sum of the digits in a two-digit number is 15, and the number is 6 more than 15 times the units digit, the number is 96. Let A and B be the digits. (A is the tens digit and B is the units digit) A + B = 15, therefore A = 15 - B 10A + B = 15B + 6Substituting for A, and solving for B...10(15 - B) + B = 15B + 6150 - 10B + B = 15B + 6150 - 9B = 15B + 6144 - 9B = 15B144 = 24BB = 6 Back substitute B into first equation and solve for A...A + 6 = 15A = 9 Therefore, the digits are 9 and 6, so the number is 96.
15
96
96
456, because they are consecutive, 4+5+6 is equal to 15, which is smaller than 20 but larger than 10, and 5 (which is in the tens place) is odd. :)
15
95 eight 10's (80) three5s (15) 80 plus 15 is 95
27. Let the first (tens) digit be x. Then, since the units digit is the tens digit plus 5, the second (units) digit is (x + 5) and the number is: 10x + (x + 5) = 11x + 5. And 3 times the sums of its digits is: 3(x + (x + 5)) = 3(2x + 5) = 6x + 15 But this is equal to the number, so: 11x + 5 = 6x + 15 ⇒ 5x = 10 ⇒ x = 2 ⇒ (x + 5) = (2 + 5) = 7 So the number is 27. Checking: 3 x (2 + 7) = 3 x 9 = 27
If the sum of the digits in a two-digit number is 15, and the number is 6 more than 15 times the units digit, the number is 96. Let A and B be the digits. (A is the tens digit and B is the units digit) A + B = 15, therefore A = 15 - B 10A + B = 15B + 6Substituting for A, and solving for B...10(15 - B) + B = 15B + 6150 - 10B + B = 15B + 6150 - 9B = 15B + 6144 - 9B = 15B144 = 24BB = 6 Back substitute B into first equation and solve for A...A + 6 = 15A = 9 Therefore, the digits are 9 and 6, so the number is 96.
15
I love these: T = tens place or first digit. U = ones place, units place, or second digit. 10T+U is the first number T+U=15 = T=15-U 10U+T is the number with the digits switched. 10U+T=10T+U+9 10U+15-U=10(15-U)+U+9 9U+15=150-10U+U+9 9U+15=159-9U 18U=144 U=8 T=15-8 T=7
150 = 15 x 10
96
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96