9:60 is one hours
it takes 15 mins to get to 60
47-15=32
9:45+47=9:45+15:32=10:00+32=10:32 AM
For this case we have the following numbers:
299
388
Let's round up each of the numbers to the nearest hundred,
We have then:
299 = 300
388 = 400
We note that now we have two numbers whose approximation is easier to add.
We have then:
300 + 400 = 700
Answer:
The sum of 299 + 388 is approximately:
700
1. Angles ADC and CDB are supplementary, thus
m∠ADC+m∠CDB=180°.
Since m∠ADC=115°, you have that m∠CDB=180°-115°=65°.
2. Triangle BCD is isosceles triangle, because it has two congruent sides CB and CD. The base of this triangle is segment BD. Angles that are adjacent to the base of isosceles triangle are congruent, then
m∠CDB=m∠CBD=65°.
The sum of the measures of interior angles of triangle is 180°, therefore,
m∠CDB+m∠CBD+m∠BCD=180° and
m∠BCD=180°-65°-65°=50°.
3. Triangle ABC is isosceles, with base BC. Then
m∠ABC=m∠ACB.
From the previous you have that m∠ABC=65° (angle ABC is exactly angle CBD). So
m∠ACB=65°.
4. Angles BCD and DCA together form angle ACB. This gives you
m∠ACB=m∠ACD+m∠BCD,
m∠ACD=65°-50°=15°.
Answer: 15°.
