we know that
using proportion
therefore
the answer is equal to
Let the unknown number be x then given,
(4/5)x - (3/4)x = 4
(16x - 15x)/20 = 4
x/20 = 4
x=80
Let the number be n.
Four fifths of the number is 4n/5.
Three fourths of the number is 3n/4.
Four fifths of a number is more than three fourths of the number by 4.
4n/5 = 3n/4 + 4
20 * 4n/5 = 20 * 3n/4 + 20 * 4
16n = 15n + 80
n = 80
Let's check.
4/5 of 80 = 4/5 * 80 = 64
3/4 of 80 = 3/4 * 80 = 60
64 is indeed 4 more than 60 showing that 4/5 of 80 is 4 more than 3/4 of 80, so 80 is correct.
Answer: 80
-4x + 5 - 5 > 29 - 5
-4x > -24
-4x/-4 > -24/-4
x > 6
What were his two mistakes?
Answer:
-4x > 24
x< 6
Step-by-step explanation:
-4x + 5 > 29
-4x + 5 - 5 > 29 - 5 (subtracted 5 on both sides)
To remove +5, Sam subtracted 5 on both sides. but 29-5 is 24
we always put the sign of greatest number . so its positive
-4x > 24 is correct
-4x/-4 > 24/-4
Dividing both sides by -4 is correct. But when we divide by negative number we need to flip the inequality sign . so > becomes <
x < 6